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国外锂离子电池设计书

Table of Contents

１Overview of Lithium Ion Batteries

●1-1. Feature of Lithium-ion Battery ●1-2. Principles of Lithium-ion Battery

２ Cylindrical Type

●2-1. Features of Battery ●2-2. Structure of Battery ●2-3. Charge Characteristics

●2-4. Discharge Characteristics ●2-5. Storage Characteristics ●2-6. Cycle Life

３ Prismatic Type

●3-1. Features of Battery ●3-2. Structure of Battery ●3-3. Charge Characteristics

●3-4. Discharge Characteristics ●3-5. Storage Characteristics ●3-6. Cycle Life

４ Safety

●4-1. General Safety ●4-2. Safety Mechanism ●4-3. Criteria of Safety ●4-4. Protection Circuit

５ Charging Method

●5-1. Charging Outline ●5-2. Charging Method ●5-3. Charging method of Assembled battery

Important Cautions for Handing Batteries

６Important Cautions for

●6-1. Outline ●6-2. Restriction on Usage ●6-3. Preparation before Use ●6-4. Non-specified Use ●6-5. Methods of Use ●6-6. Maintenance and Inspection ●6-7. Countermeasures

●6-8. Precautions for the Design and Installation into Equipment Incorporated Lithium-ion Batteries ●6-9. Regarding to Recycle ●6-10.　Others●6-11. Cautions to be indicated on Lithium-ion Battery

７ Glossary

1 Overview of Lithium Ion Batteries

1- 1Feature of Lithium-ion

Battery

1-2Principles of Lithium-ion Battery ■1-1Feature of Lithium-ion

B attery

Lithium secondary battery is a general term of battery that uses lithium metal, lithium alloy or material absorbing lithium ion for negative active material.

Lithium-ion battery uses carbon material for the anode and lithium ions exist in the carbon material. It means that there is no metallic lithium at any state of charge during normal usage. In order to differentiate from the batteries that use lithium metal or lithium alloy as the anode, it is called Lithium-ion battery. Main features of SANYO Lithium-ion battery are as follows.

(1)High energy density with volumetric energy

density 1.5 times higher and gravimetric energy density 2 times higher than that of high capacity model of Ni-Cd battery. This means that Lithium-ion battery is much more suitable for lighter or smaller portable applications.

(2)Voltages are high with average operating voltages

at 3.6 to 3.7V and these are approximately the same as three cells in series of Ni-Cd or Ni-MH batteries. It means that using Lithium-ion batteries reduces the number of cells in actual use.

(3)Discharge curves are flat because of highly

crystallized carbon graphite used as the anode. (4)Long cycle life normally 300 to 500 charge

discharge cycles can be achieved.

(5)Self-discharge is 10W, approx 2% / month at room

temperature.

(6)There is no memory effect as in Ni-Cd batteries.

(7)Safety is high due to no metallic lithium content

and improved structures.

■1-

1-22Principles of Lithium-ion

Battery

●1-

1-22-1

-1 Mechanism of

Mechanism of c c harge

harge /

d ischarge

Lithium-ion batteries do not use metallic lithium, so battery life is not reduced by internal short circuit caused by Lithium dendrites, which was the main weakness of other lithium secondary batteries. Furthermore the chemical stability of carbon anode, even fully charged is higher than metallic lithium. Therefore Lithium-ion batteries are safer systems. Lithium-ion battery consists of lithium cobaltate cathode, graphite anode, organic solvent electrolyte including lithium salt and separator.

Fig.1-1 shows schematic for chemical reactions of Lithium-ion batteries. Both electrodes have layered structure, and when charging, lithium ions come out from the cathode and move through electrolyte to be deposited in between the layers of the graphite anode.When discharging the reaction is revised.

Reactions of charge and discharge are follows.

Reactions of Lithium-ion Battery

Lithium ions are the medium by which electrons are carried and are included in positive electrode materials.There is no need to treat metallic lithium in assembling Li-ion cells. During the charging process,lithium ions in the positive electrode transfer into the negative electrode and are placed between the layers of graphite, which makes electrical potential difference.Since cells are partially charged during the production process for shipping purposes, the formula shown above can more accurately represented by 1-xCo 2/CyLix.

Fig.1-1:Diagram Diagram showing showing reaction of Lithium-ion battery when battery when charging/ charging/ charging/discharging.discharging.

●1-1-22-2-2 Differences from Nickel

Cadmium and Nickel Metal Hydride batteries

Ni-Cd and Ni-MH batteries are using alkaline aqueous electrolyte and hydro oxide ions carry the electrical charges. During charging water is created and oxygen gas is generated, so the charge/discharge process loses efficiency to below 100%. However, this sub-reaction can prevent overcharging enabling the manufacture of sealed batteries.

Conversely Lithium-ion batteries charge/discharge process is practically 100% efficient except the first charge/discharge cycle, but this is a disadvantage in overcharge and over-discharge.

Lithium-ion batteries use an organic solvent for the electrolyte which is different from alkaline rechargeable batteries and the conductivity being lower makes high rate discharge difficult. This is

overcome by using larger area electrodes.

●1-1-22-3 Method of manufacturing

In order to ensure high performance and safety,there are many complicated manufacturing processes,and batteries are made in a carefully controlled environment using strictly controlled and maintained equipment.

The electrodes are manufactured using active materials, conductive agents and binder which are mixed with liquid. These mixtures are then uniformly coated onto the thin metal foil, then after drying, the electrodes are cut down to the designated sizes.

The cathode and anode electrodes are then wound together with a separator and inserted into a can and the electrolyte is filled. The sealing completes the battery assembly.

Prior to shipping the batteries to customers, the batteries will undergo an aging process, thorough inspections, initial charge/discharge cycle, etc.,ensuring the highest quality of product is maintained.

●1-1-22-4 Cathodes

Materials containing lithium ions and which can be used the cathode active material must be capable of deintercalation of lithium ions during charge and intercalation of lithium ions during discharge. Lithium cobaltate (LiCoO 2) is used mainly in the marketplace and it is known that lithium nickelate (LiNiO 2) or lithium manganate (LiMn 2O 4) are also used for the cathode. Fig.1-2 shows comparisons of discharge characteristics for various cathode materials.

SANYO is using lithium cobaltate as the cathode because of its good reversibility, capacity, efficiency,voltage and flat discharge characteristics.

Fig.1-2: Discharge characteristics of different

positive materials

C C ( Positive Electrode )

LiCoO 2

Li 1-x CoO 2+ xLi ++ xe

( Negative Electrode )y +xLi +

+ xe -

y Li x

( Overall )

LiCoO 2+ C y

Li 1-x CoO 2+ C y Li x

Negative Positive Li +

Electrode

6080100120

Capacity(%)

2.5

33.544.5

C e l l V o l t a g e (V )

●1-1-22-5 Anodes

In order to create Lithium-ion batteries with higher energy density using carbon anodes, it must use a carbon material having large lithium storage capability.

Presently, two types of carbon materials are used.One is highly crystallized carbon like graphite and the other is amorphous carbon like coke. C 6Li is equivalent to a lithium ion doped in a hexagonal ring of carbon atoms, and its theoretical capacity is 372mAh/g. Highly crystallized carbon can obtain large capacity and graphite can obtain the capacity close to the theoretical value. The biggest difference between coke and graphite is discharge characteristics, and these characteristics are compared in Fig.1-3.

Fig.1-3: Discharge characteristics of different

negative negative materials materials

Using the coke system, remaining capacity can

easily be measured using the discharge curve,however graphite system is superior in terms of its fundamental purpose of supplying more energy .

SANYO is using graphite as the anode for the above mentioned reasons.

●1-1-22-6　Separators

Major functions of battery separators are to insulate positive and negative electrodes, retain the electrolyte and transmit lithium ions. To ensure functionality the separator needs to have the following characteristics;(1) Electrical insulation

(2) Chemical and thermal stability against electrolyte

(3) Capability of holding electrolyte

(4) Porous for transmission of lithium ions (5) Thinness and mechanical strength

Polyethylene and polypropylene porous thin films are generally used as suitable materials for above-mentioned requirements. The pores of these films melt and prevent the lithium ions from passing through the separator at certain temperature, which makes a major contribution to safety of Lithium-ion

batteries as instructed in section 4-2.

●1-1-22-7 Electrolyte

Electrolyte carries out the essential role of carrying lithium ions (which means current flow).

In case of lead acid for Ni-Cd and Ni-MH battery,aqueous solution is used as electrolyte. However,because Lithium-ion battery is used at high voltages over 4V , which causes electrolysis of water, lithium salt in nonaqueous organic solvent is appropriate for electrolyte. The organic solvent is required to satisfy the following characteristics.

(1) High conductivity of lithium ion

(2) Electric chemical stability (at over 4V)(3) Chemical and thermal stability (4) Wide temperature rage

Due to voltages over 4V , only limited types of solvent are suitable for Lithium-ion batteries. As for electrolyte salt, it is necessary to increase the conductivity of electrolyte and LiPF6 in mixed solvent mainly including ethylene carbonate is generally used.

●1-2-1-2-88 Materials for Can

Material for can of positive side have to withstand

Lithium-ion’s high voltage of over 4V . Stainless can be used for 3V , but Lithium-ion battery (cylindrical type) adopts nickel-plated iron for over 4V . On the other hand, Sanyo pioneered and has been leading the lightening competition by using aluminum alloy for outer can (negative) of prismatic types.

2.5

3.5C e l l V o l t a g e (V )

C e l l V o l t a g e (V )

2 Cylindrical Type

2-1Features of Battery

2-2Structure of Battery

2-3Charge characteristics

2-4Discharge characteristics 2-5Storage characteristics 2-6Cycle Life ■2-1Features of Battery

Standard cylindrical type was the first produced type in Lithium-ion history. Cylindrical types are used mainly in multi-series and parallel configurations for personal computers, camcorders, etc.

In general, cylindrical types have shorter width (diameter) and more capacity than prismatic types. This is why cylindrical types are very prefered when high capacity is needed for long tube-shaped space, such as a hinge of notebook PC.

■2-2Structure of Battery

Fig.2-1 shows the structure of Sanyo’s cylindrical type Lithium-ion cell.

Fig.2-1: Internal structure of Battery

As already mentioned, electrodes are a spirally wound roll consisting of very thin sheets of positive and negative electrode and high polymer separators. Therefore cylindrical cells have an efficient structure which allows for a good performance for energy density, charge/discharge characteristics, and temperature characteristics.

The electrolyte is an organic solvent with high voltage stability mixed with lithium salt.

In order to keep safety in case of abnormal use, the cell has some protective parts in it such as PTC device, gas release vent, or special separator.

PTC has a combined function of current fuse and thermal fuse. When over-current flows through the PTC, self-heating increases its resistance. In a case like that, the resistance will go up to some 10k ohm, which controls abnormally large current. Cylindrical cells have a ring-shaped PTC in its sealing cap, which prevents excess current(e.g. by short-circuit) from causing abnormal heating of the cell.

In addition, the cell is equipped with a current interrupt device(CID) combined with a gas release vent. This will stop charging when pressure increases

in the cell and the cell will vent in case of further increase in pressure. Fig.2-2 shows the structure of it. The top of the vent is welded to positive cap No.2.

When the vent is raised up by pressure in the cell, it will be removed from positive cap No.2 and current will never flow.

Fig.2-2: Structure Diagram of Sealing Parts

For separator, micro-porous polymer film is adopted based on the know-how of Lithium primary battery for cameras. The separator has current-interrupting function. If abnormal use (such as short-circuit) causes excess heat of the cell, meltdown will shut down the pores and restrain the flow of lithium ions.

Cylindrical cell is assembled and sealed using these kinds of functional parts.

■2-3Charge Characteristics

●2-3-1　Outline

Charge is the operation that makes the discharged battery reusable. Normally Lithium-ion battery is charged by constant current-constant voltage (CC-CV) method. For CC-CV charging, chargers need to control Max charge voltage, which is 4.2 +/- 0.03V(4.2+/- 0.05V in special cases) for Sanyo’s Lithium-ion batteries.

Fig.2-3 shows typical charge characteristics of Lithium-ion battery.

Fig.2-3　Charge Characteristics

When a battery is charged with CC-CV (1C-4.2V),

it is charged with constant current of 1C and the cell voltage gradually goes up to the controlled voltage(4.2V) in about 50 minutes. At this point, state of charge is about 80%. After that, CV charging starts and charge current decreases. Charging is completed in about 2.5 hours.

●2-3-22-3-2 Charge Condition Charge Conditions s and Charge

Time

Fig.2-4 shows charge characteristics depending on charge current.

Fig.2-4: Fig.2-4: Charge current Charge current Charge current and Charge capacity and Charge capacity

When charging at higher currents, the cell voltage rises more quickly. This is because of the rise of over-voltage in electrode reactions, and the rise of voltage caused by the internal resistance of the cell.Therefore, larger charge current will decrease the time of CC area. However, if the constant current is over 1C, current value makes no big differences on total time for 100% charge because percentage of CV area becomes much longer. Normal charge current for this battery is between 0.2C and 1C.

Fig.2-5 shows ambient temperature- charge amount characteristics.

Fig.2-5: A Fig.2-5: Ambient temperature mbient temperature mbient temperature and and and C harge amount

The cell voltage depends on ambient temperature.The lower the ambient temperature, the higher the cell voltage because of the increase of over-voltage in electrodes reactions. The point is that charging at under 0deg.C is not practical because it takes long time to reach 100% charged state. The normal charge temperature is between 0 and 40deg.C.

Also charge capacity depends on the charge end current. Fully charged state can be defined as charging terminated by current under 0.02C – https://www.wendangku.net/doc/908815530.html,rger terminating current means more room for charge.

Gas Release Vent

Welding

PTC

Sealing Cap Gasket

Current Interrupt Device

Charge Time / hour

2.0

2.5

3.03.5

4.0

4.5

C e l l V o l t a g e / V

0.250.50.751

1.25C u r r e n t / C A

5075100

C a p a c i t y / %

Charge Time / hour

2.0

2.5

3.03.5

4.0

4.5

C e l l V o l t a g e / V

0.511.52

2.5C u r r e n t / C A

5075100

C a p a c i t y / %

Charge Time / hour

2.0

2.5

3.03.5

4.04.5

C e l l V o l t a g e / V

0.250.50.751

1.25C u r r e n t / C A

5075100

C a p a c i t y / %

020

406080100120

D i s c h a r g e C a p a c i t y / %

2.0

2.5

3.0

3.5

4.0

4.5

C e l l V o l t a g e / V

100

C a p a c i t y / %

not used for long periods.

Please consult Sanyo on details because it depends on battery pack design (e.g. cell configuration,protection circuit).

■2-6Cycle Life

●2-6-1Outline

In general, end of cycle life of secondary batteries is defined when capacity falls below 60% of the nominal capacity and no longer recovers by subsequent cycles. Cycle life largely depends on the cycle conditions such as charge, depth of discharge,current and ambient temperature.

Fig.2-12 gives an example of cycle characteristics.

Fig.2-12: Cycle Fig.2-12: Cycle Characteristics Characteristics

Conditions that will reduce cycle life. -Over-charging with excessive voltage -Continuous charging

-Charging and discharging with excessive current -Over-discharging to protection working voltage

-Ambient temperature out of the recommended range.

Unlike other kind of secondary, Lithium-ion batteries do not suffer from memory effect.

●2-6-2Factors Factors affecting affecting affecting Cycle Life Cycle Life

(1) Reasons for Battery Cycle Life Reduction

Cycle life is determined mainly by the degradation of electrolyte causing a rise in internal resistance and decline of reversibility of electrode active materials.

These kinds of phenomena are accelerated when charge-discharge conditions recommended by Sanyo are not maintained.(2) Battery Temperature

Cell temperature is one of the factors that make a difference on cycle life of Lithium-ion battery.Sanyo’s recommendation is 0-40deg.C for charge and 0-60deg.C for discharge.

Long-term storage of charged cells at high temperature also shortens the cycle life.(3) Condition of Charge

Fig.2-13 shows the relationship between cycle number and charging voltage curve. After cycling,the CC area reduces and the CV area becomes extended. This transition occurs due to increase of internal resistance caused by charge-discharge cycles.

Fig.2-13: Cycle Fig.2-13: Cycle Characteristics Characteristics Characteristics (Charge) (Charge)

Above mentioned is referring to full charge-discharge. However, in practical use, shallow charge-discharge is used in most cases. Lithium-ion batteries have no memory effect like Ni-Cd and Ni-MH. Then, let us explain about shallow charge-discharge cycle characteristics. In a case of, for example, an experimental regular cycle of full charge - 50% discharge cycle, the cycle life is about twice as long as normal full cycle. This is shown in fig.2-14.

Fig.2-14: Cycle Fig.2-14: Cycle Characteristics Characteristics Characteristics (Depth of (Depth of

Discharge)

Lithium-ion batteries have the regulated controlled charge voltage. Charging by voltage beyond the controlled voltage (over-charge) can deteriorate cycle life. And that also could cause heat, explosion and fire because of abnormal reactions inside the cell.

Continuously charging without time control also reduces cycle life. Charging should be stopped at a given time limit or when a specific current is reached.

Number of Cycle

20406080100120

D i s c h a r g e C a p a c i t y / %

Charge Time / hour

2.0

2.5

3.03.5

4.04.5

C e l l V o l t a g e / V

0.250.50.7511.25

C h a r g e C u r r e n t / C A

5075100

C h a r g e C a p a c i t y /

Number of Cycle

D i s c h a r g e C a p a c i t y / %

(4) Condition of Discharge

After several hundreds cycles, discharge voltage of Lithium-ion batteries reduces. Fig.2-15 shows relationship between number of cycles and discharge characteristics. The reason for this voltage change is due to the increase of internal resistance brought about by cycling.

Fig.2-15: Cycle Fig.2-15: Cycle Characteristics Characteristics Characteristics ( ( (Discharge Discharge

Characteristics Characteristics))

Discharge Capacity / %

2.0

2.5

3.0

3.5

4.0

4.5

C e l l V o l t a g e / V

3 Prismatic Type

3-1Features of Battery

3-2Structure of Battery

3-3Charge characteristics

3-4Discharge characteristics 3-5Storage characteristics 3-6Cycle Life

■3-1Features of Battery

In connection with small and light weight-sizing of applications, the battery used as the power supply has also been asked for less-space, light　weight and a high performance. Following this trend, prismatic type has been developed, keeping the good features of cylindrical type.

Based on Sanyo’s cylindrical technology and adding new innovative technologies, the prismatic type achieved the goal of giving light weight and high capacity.

Light weight was achieved by using aluminum alloy for the case increasing the energy density by 30% in comparison to batteries using a steel case. Using the aluminum can for prismatics compensates for any weight increase which would have occurred when changing battery form from cylindrical.

The aluminum can and laser welding technologies are very complex. But Sanyo developed and pioneered these technologies and brought light weight products to market ahead of our competitors. Sanyo continues to improve the technology by bringing products that are lighter with even increasing capacity.

■3-2Structure of Battery

Fig.3-1 shows the structure of Sanyo’s prismatic type Lithium-ion cell.

Fig.3-1: Internal structure of Battery

The electrodes are manufactured as mentioned in section 1-4-2.

Prismatic cells are essentially made the same as cylindrical cells. The wound electrodes, with a separator in between is compressed and inserted into the case which is then closed with a sealing plate.

To reduce weight, an aluminum can is used as the case. The sealing plate is laser welded to the can ensuring high reliability against leakage.

Same as cylindrical cells, prismatic cells are equipped with a gas release vent to release the internal gas in case pressure increases in the cell. Electrolyte

Case

■3-3Charge Characteristics

●3-3-1　Outline

Charge is the operation that makes the discharged battery reusable. Normally Lithium-ion battery is charged by constant current-constant voltage (CC-CV) method. For CC-CV charging, chargers need to control Max. charge voltage, which is 4.2 +/-0.03V(4.2 +/- 0.05V in special cases) for Sanyo’s Lithium-ion batteries.

Fig.3-2 shows typical charge characteristics of Lithium-ion battery.

Fig.3-2　Charge Characteristics

When a battery is charged with CC-CV (1C-4.2V),it is charged with constant current of 1C and the cell voltage gradually goes up to the controlled voltage(4.2V) in about 50 minutes. At this point, state of charge is about 80%. After that, CV charging starts and charge current decreases. Charging is completed in about 2.5 hours.

●3-3-23-3-2 Charge Condition Charge Conditions s and Charge

Time

Fig.3-3 shows charge characteristics depending on charge current.

Fig.3-3: Fig.3-3: Charge current Charge current Charge current and Charge capacity and Charge capacity

total time for 100% charge because percentage of CV area becomes much longer. Normal charge current for this battery is between 0.2C and 1C.

Fig.3-4 shows ambient temperature- charge amount characteristics.

Fig.3-4: A Fig.3-4: Ambient temperature mbient temperature mbient temperature and and and C harge amount

●3-3-33-3-3 Prec Prec Precautions for Charging autions for Charging

Do not continuously charge, otherwise battery performance will deteriorate. Also, the charger needs to be designed on the same basis. (Refer to section5 ”Charging method” for more details.)

■3-4Discharge Characteristics

●3-4-1　Outline

Discharging voltage of Lithium-ion batteries changes depending on discharge current, ambient temperature and other conditions, but it is 3.7V on average, which is about 3times that of Ni-Cd and Ni-MH. This higher discharging voltage is one of the major advantages of lithium-ion. For example,appliances driven by 3-4V need 3series of Ni-Cd or Ni-MH whereas only 1 series of Lithium-ion is needed.

Charging Time (hrs)

2.0

2.5

3.03.5

4.0

4.5

C e l l V o l t a g e (V )

0.250.50.751

1.25C u r r e n t (C A )

5075100

C a p a c i t y (%)

Charge Time (hrs.)

2.0

2.5

3.03.5

4.04.5

C e l l V o l t a g e (V )

0.250.50.751

1.25C u r r e n t (C A

)

5075100C a p a c i t y (%)

Charging Time (hrs)

2.0

2.5

3.03.5

4.04.5

C e l l V o l t a g e (V )

0.250.50.751

1.25C u r r e n t (C A )

5075100

C a p a c i t y (%)

●3-4-2　Discharge Rate

Fig.3-5 and 3-6 show the relation between discharge rate, voltage and capacity.

Fig.3-5: Fig.3-5: Discharge Rate Discharge Rate Discharge Rate (Rate) (Rate)

Fig.3-6: Fig.3-6: Discharge Characteristics Discharge Characteristics Discharge Characteristics (Rate) (Rate)

Fig.3-8: Fig.3-8: Discharge Characteristics Discharge Characteristics Discharge Characteristics ( ( (Temperature Temperature Temperature))

Discharge capacity at high temperature is equal to

or larger than at room temperature, but the capacity at low temperatures decreases because low ambient temperature lowers reactivity of the electrode and cell voltage. This capacity deterioration is just temporary. The performance will recover at room temperature. The ambient temperature and the condition of discharge current vary by configuration of assembled battery same as cylindrical type, the actual battery pack to be checked.

●3-4-4　Over-discharge

Over-discharge leads to deterioration of performance. Use Lithium-ion batteries over the recommended voltage limits.

In extreme cases that an assembled battery is deeply discharged, polarity of the cell with the lowest capacity will be reversed because the cells which compose the assembled battery have small differences of capacities. Repeated deep discharge could cause rapid deterioration of performance. Do not over-discharge batteries to avoid polarity reversal.For this reason, recommended discharge end voltages are listed below.

For 1 series( 3.7V) connection: 2.75V or higher For 2 series( 7.4V) connection: 6.0V or higher For 3 series(11.1V) connection: 9.0V or higher For 4 series(14.8V) connection: 12.0V or higher In addition, each assembled battery is equipped with over-discharge protection circuit, which sets up the over-discharge limit voltage (2.0-2.4V). (Refer to section4 ”Safety ” for more details.)

■3-5Storage Characteristics

●3-5-1Outline

Even when disconnected from a load after being

charged, batteries lose their energy through self-discharge, which leads to capacity loss and lower voltage. The self-discharge of Lithium-ion battery is about 3%/month for 100%-charged state at room temperature, which is less than Ni-Cd and Ni-MH.Self-discharge rate depends on state of charge of battery and ambient temperature during storage.Practical self-discharge rate includes consumption

Discharge Current (CA)

C a p a c i t y (%)

C e l l V o l t a g e (V )

Ambient Temperature ( )

D i s c h a r g e C a p a c i t y (%)

Discharge Capacity (%)

2.0

2.5

3.0

3.5

4.0

4.5

C e l l V o l t a g e (V )

current of protection circuit that is built in assembled batteries.

●3-5-2Storage Temperature

The relationship between storage temperature and residual capacity is shown in Fig.3-9.

High temperature increases the self-discharge rate.

Fig.3-9: Storage Fig.3-9: Storage Characteristics Characteristics Characteristics (R (R (Residual esidual

capacity capacity rate) rate)

The higher the state of charge, the lower the amount of capacity becomes recoverable. Higher storage temperature increases the differences. In other words, recoverable capacity depends on the state of charge. The lower the state of charge, the more capacity can be recoverable. If stored at discharged state, except for over-discharged state,Lithium-ion battery can recover 100% capacity even at storage temperature of 60deg.C.

A decline of recoverable capacity rate is also caused by long-term storage at over-discharged state of below 1V . This phenomenon appears earlier at higher

storage temperature. The reason is that higher temperature accelerates self-discharge and will reduce the time taken for the cell voltage to reach 1V .This is why Sanyo recommends that Lithium-ion battery is stored at low temperature and at discharged state unless it becomes over discharged state.

●3-5-4Prec Precautions for Storage autions for Storage

In order to optimize Lithium ion battery’s performance, compliance with following conditions is recommended.

(1)Storage Temperature, Humidity

Ensure that the batteries are stored in non-condensing atmosphere with no corrosive gas.(Humidity 65+/-20%)

Less than 30days: -20 to 50deg.C 30 – 90days : -20 to 40deg.C

More than 90days: -20 to 30deg.C

Do not store out of above listed temperature range and/or at extremely high humidity, or leakage and rust could happen.

(2) Long-term Storage

Even though over-discharge protection is built into each battery pack, if it is stored connected to a load, the recoverable capacity rate tends to reduce because it takes shorter to fall down to over-discharge protection working voltage. For this reason, disconnect battery from load in a case of long-term storage, or battery could not be fully charged and the recoverable capacity rate could be deteriorated.

Charge about 10% every 6months if the battery is not used for long periods.

Please consult Sanyo on details because it depends on battery pack design (e.g. cell configuration,protection circuit).

■3-6Cycle Life

●3-6-1Outline

Fig.3-11 gives an example of cycle characteristics.

Storage Period (month)

100

R e c o v e r y C a p a c i t y (%)

C a p a c i t y (%)

Fig.3-11: Cycle Fig.3-11: Cycle Characteristics Characteristics

Conditions that will reduce cycle life. -Over-charging with excessive voltage -Continuous charging

-Charging and discharging with excessive current -Over-discharging to protection working voltage

-Ambient temperature out of the recommended range.

Unlike other kind of secondary, Lithium-ion batteries do not suffer from memory effect.

●3-6-2Factors Factors affecting affecting affecting for Cycle Life for Cycle Life

(1) Reasons for Battery Cycle Life Reduction

Cycle life is determined mainly by the degradation of electrolyte causing a rise in internal resistance and decline of reversibility of electrode active materials.

These kinds of phenomena are accelerated when charge-discharge conditions recommended by Sanyo are not maintained.(2) Battery Temperature

Cell temperature is one of the factors that make a difference on cycle life of Lithium-ion battery.Sanyo’s recommendation is 0-40deg.C for charge and 0-60deg.C for discharge.

Long-term storage of charged cells at high temperature also shortens the cycle life.(3) Condition of Charge

Fig.3-12: Cycle Fig.3-12: Cycle Characteristics Characteristics Characteristics (Charge) (Charge)

Above mentioned is referring to full charge-discharge. However, in practical use, most case is shallow charge-discharge. Lithium-ion battery has no memory effect like Ni-Cd and Ni-MH. Then, let us explain about shallow charge-discharge cycle characteristics. In a case of, for example, a experimental regular cycle of full charge - 50% discharge cycle, the cycle life is about twice as long as normal full cycle. This is shown in fig.3-13.

Fig.3-13: Cycle Fig.3-13: Cycle Characteristics Characteristics Characteristics (Depth of (Depth of

Discharge)

Continuously charging without time control also reduces cycle life. Charging should be stopped at a given time limit or when a specific current is reached.(4) Discharge Conditions

After several hundreds cycles, discharge voltage of Lithium-ion batteries reduces. Fig.3-14 shows relationship between number of cycles and discharge characteristics. The reason for this voltage change is due to the increase of internal resistance brought about by cycling.

Charge Time (hrs.)

2.0

2.5

3.03.5

4.04.5

C e l l V o l t a g e (V )

0.250.5

0.751

1.25C u r r e n t (m A )

5075100

C a p a c i t y (%)

Number of Cycles

D i s c h a r g e C a p a c i t y (%)

Number of Cycles

20406080100120

D i s c h a r g e C a p a c i t y (%)

Fig.3-14: Cycle Fig.3-14: Cycle Characteristics Characteristics Characteristics ( ( (Discharge Discharge

Characteristics Characteristics))

Discharge Capacity (%)

2.0

2.5

3.0

3.5

4.0

4.5

C e l l V o l t a g e (V )

4 Safety

4-1General Safety

4-2Safety Mechanism 4-3Criteria of Safety 4-4Protection circuit

■4-1General Safety

While a Lithium-ion battery exhibits the advantages of high energy density and high voltage, unlike the conventional metal lithium battery, it ensures high safety. As the name Lithium ion implies, no lithium metal or alloy is present and lithium exists only in state of ions.

However, Lithium-ion batteries contain combustible materials so to ensure maximum safety, strict tests and examinations are performed in case of application failure or misuse.

Moreover, the battery is protected from over charge, over discharge, and over-current by incorporating a protection circuit when it is assembled to the complete pack.

Batteries supplied by Sanyo satisfy the guideline of safety for lithium rechargeable batteries and are approved by UL standards which is the organization evaluating body for 3rd party products.

4-2Safety Mechanism

The cylindrical type of Lithium-ion battery is equipped with safety mechanisms, such as a current interrupt device, a gas release vent, and protection device like a PTC, in the battery.

(1)Gas release vent with current interrupt device

Fig4-1 shows the current interception for

cylindrical type of lithium ion battery.

Fig.4-1:

Fig.4-1: Current Interrupt Device

Current Interrupt Device

The gas release vent works when the internal pressure rises with abnormal heat generation or over charge by failure of all of charger, protection circuit and protective device.

Top part of gas release vent is welded on positive cap 2, and the safety is secured with no conductivity lifting and detaching the vent from the welding.

This function is for disconnecting the load by force when it is charged abnormally.

Gas Release Vent

Welding

PTC

Positive Cap 2

Sealing Cap Gasket

Current Interrupt Device

If the battery is exposed to extreme high temp and the internal pressure increases rapidly, the gas release vent works and the gas inside is released safely.

(2) PTC

PTC has 2 functions. It serves as a current fuse and a thermal fuse. Internal resistance increases with heat generation with high current flow. The value of internal resistance depends on the size of the element. Normally it is several 10m and if value increases to several 10k it trips to limit the current. Cylindrical type have round PTC inside of the sealing plate and it prevents abnormal heat generation when the current flows at a high rate caused by external short circuit or other reason.

(3) Separator

A separator is a micro porous film of high polymer that is based on technologies for lithium batteries used in cameras. When abnormal heat is generated by external short circuit or other condition, the pores in the separator seal-up due to the separator melting. This cuts off the current.

(4) Thermal Fuse

Certain models of prismatic Lithium-ion batteries are equipped with current interruption devices such as thermal fuses.

For assembled battery packs, the protection circuit is incorporated to prevent over-charge, over-discharge and over-current. A thermal fuse or PTC can be added when necessary.

4-3Criteria of Safety

Batteries supplied by Sanyo satisfy the guideline of safety for lithium rechargeable batteries and are approved by UL standards which is the organization evaluating body for 3rd party products.

The test requirements of Battery Association of Japan are as follows.

Test Items of Battery Association of Japan

4.3.(1) Electrical Test

External Short Circuit Test: No explosion or fire

after having 6hours short

circuit made with less than

50m? lead between terminals. Forced Discharge Test: No explosion or fire after

250% forced discharge of

rated capacity. The test

may be stopped when the

current flow is prevented

by operation of protection

parts which are in the

battery. Continuous Charge Test: No safety vent operation,

deformation, explosion or

fire after being

continuously charged for 1

month in conditions

recommended by Sanyo. Over Charge Test: No explosion or fire after 250%

charge with Sanyo recommended

current. The test may be stopped

when the current flow is prevented

by operation of protection parts

which are in the battery.

Over Current Test: No explosion or fire after having

100% charge of rated capacity

with 3 times as much as Sanyo

recommended charge current.

The test may be stopped when the

current flow is prevented by

operation of protection parts

which are in the battery.

4.3.(2) – I Mechanical Test

Vibration Test: No deformation, explosion or fire with

vibration for 90 - 100 minutes in the

XYZ direction with the amplitude of

0.8mm, frequency 10 to 55Hz

sweeping speed 1Hz/in.

Impact Test: No deformation, explosion or fire with a

impact on XYZ direction, which the

minimum acceleration for initial 3ms is

75g and the peak acceleration is

between 125g and 175g.

Drop Test: No explosion or fire when dropped at random 10 times onto the concrete floor

from 1.9m height.

4.3.(2) – II Mechanical Test = Abnormal Abuse

Nail Test: No explosion or fire for 6hours after penetrated by 2.5 to 5mm diameter nail

at center of / perpendicular to the cell . Crush Test: No explosion or fire with 13kN pressure

having battery in between 2 flat iron

plates.

Impact Test: No explosion or fire when the impact of

9.1kg weight drops from 61cm height

onto the battery which has 7.9mm

diameter bar placed on it vertically to

top terminal direction.

Drop Test: No explosion or fire when dropped at random onto the concrete floor from 10m

height.

4.3.(3) – I Environmental Test

High Temp. Storage: (a) No explosion or fire with

5hours storage in 100

followed by 24 hours in 20 .

(b) No explosion or fire with

30days storage in 60

followed by 24 hours in 20 .

Temp. Cycle Test: No explosion or fire with 10 cycles

of 2hours storage in -20 and 2hours storage in 60 .Low Pressure Test: No explosion or fire when left in

11.6kPa atmosphere absolute for 6hours .4.3.(3) – II Environmental Test = Abnormal Abuse Heating Test: No explosion or fire with 60min.

heating in an oven at 130 which raised at a rate of 5 2 /min.

Immersion Test: No explosion or fire with 24 hours

immersion in water at room temperature.

4-4 Protection Circuit

The protection circuit to control charge and discharge is built into Sanyo Lithium-ion battery pack. By incorporating the protection circuit, the battery is protected from over-charge, over-discharge and over-current.

Although there is a basic specification of the protection circuit, a detailed specification may be customized to suit the application.

Also the protection circuit is customized if the pack configuration (e.g. terminal position, shape) is different from other packs considering the productivity, but the function and the circuit remain the same.

Fig 4-2 shows one example of the basic operation of protection circuit.

Fig.4-2:Lithium Lithium--ion Battery for PCB ion Battery for PCB Work Flow Chart

(Over-Charge Protection)

It protects the battery from over-charge by misuse or charger failure. The over-charge is generally detected and the charging is stopped at Typ. 4.28-4.35V/cell.

The over-charge protection is released and reset when the voltage is dropped to Typ. 4.20V/cell.

(Over-Discharge Protection)

If a Lithium-ion battery discharges to about 0V or is left for a long period in the discharged state less than 1.0V , it will cause performance degradation. Therefore the over-discharge protection is equipped in the assembled battery pack. The voltage which detects over-discharge is usually set at Typ. 2.30V/cell.

The over-discharge protection is released and reset when the voltage rises more than Typ.2.3V/cell.

(Over-Current Protection)

In order to protect the protection circuit and the battery from over-current discharge, the over-current protection is equipped. It is set up so that it operates around 2A current flows usually.

The over-current protection is released and reset when the battery is charged again.

Normal Condition

Increases, above 4.30Cell voltage increases over Discharge more equipment or charging

decreases, below 4.20decreases, below 2.304.2Overcharge protection works (charge impossible)

(charge-discharge possible)

Cell voltage

0.03V

Overdischarge

protection works (discharge impossible)

2.24 2.41V by charging

Overcurrent protection works (discharge impossible)

than Approx. 2A

Release from

Cell voltage

0.05V

Cell voltage

0.06V

V Charge

5 Charging Method

5-1Charging Outline

5-2Charging Method

5-3Charging method of assembled battery

■5-1Charging Outline

Generally, charging of Lithium-ion batteries is performed by constant current constant voltage charging method. Although amount of charge depends on charging voltage, exceeding each regulated value for current or voltage is forbidden. When charging starts with constant current and battery voltage reaches its designated value, it will change to constant voltage charging. The charging current begins attenuation and battery voltage approaches to fully charged state for regulated voltage. Charging by constant current need not to be precise and semi-CC is allowed. However, charging by constant voltage should be regulated precisely not to affect charging capacity or overcharge.

Generally, higher current value for constant current area is thought to reduce total charging time. Despite charging at higher rate only means reaching voltage limit earlier, the overall charging time to reach full charge will remain almost the same. It is preferable that charging current is set to 0.5 -1C. Lower charging current value is also advantageous to cycle life. Battery charging is also affected by temperature and when charging at low temperatures the charging time will be extended. Charging at low temperature is not forbidden but best avoided.

■5-2C harging

harging M M ethod

Generally, charging of Lithium-ion batteries is by constant current - constant voltage charging method. Since constant current-constant voltage charge is a charging method which controls charging voltage, charging voltage is usually set 4.2V.

Fig. 5-1 shows the general charging characteristics for prismatic type Lithium- ion battery.

Fig.5-1: Charge Characteristics

Constant current charge is continued for 50 minutes, and when battery voltage reaches 4.2V, it changes to constant voltage charge. Full-charged state is judged from two methods. One is defined by charging time, and the other is by charging current value (reduced current value in constant voltage area). For example, in Fig. 5-1, when charging time

Charging Time (hrs)

2.0

2.5

3.0

3.5

4.0

4.5

(

)

0.25

0.5

0.75

1.25

(

)

100

(

)

锂离子电池规格书

锂离子电池规格书 Specification For Lithium Ion Rechargeable Battery 电池型号（Type）：383450AH 标称容量（Rated Capacity）：700mAh 部门（Department）：铝壳制造部生效日期（Effective Date）：2007-3-12

1. 范围SCOPE AND APPLICATION 本标准规定了锂离子电池的定义、技术要求、测试方法及注意事项。本标准适用于深圳市山伊克斯技术有限公司生产的锂离子电池。 This specification describes the definition, technical requirement, testing method, warning and caution of the lithium ion rechargeable battery. The specification only applies to battery supplied by Shenzhen 3EX TECH. Co., Ltd. 2. 定义 DEFINITION 2.1 额定容量：指在20±5℃，65±5%RH 环境下，以5小时率放电至终止电压时的容量，单位毫安时(mAh)。 Rated Capacity: Under 20±5℃，65±5%RH, it means the capacity value of being discharged by 5hrs ratio to End Voltage. 2.2 终止电压：放电终止时的规定电压为2.75V 。 End voltage: The end voltage of discharge is 2.75V ，which is defined specially. 2.3 0.2倍率充电：指在20±5℃，65±5%RH 环境下，以140mA 电流恒流充电至单体电池电压4.2V 后，转为恒压 4.2V 充电，至充电电流小于10±5mA ，停止充电。 0.2 Charge method: Under 20±5℃，65±5%RH, it can be charged to 4.2V with constant current of 140mA, and then, charged continuously with constant voltage of 4.2V until the charged current is less than 10±5mA. 2.4 0.5倍率充电：指在20±5℃，65±5%RH 环境下，以350mA 电流恒流充电至单体电池电压4.2V 后，转为恒压 4.2V 充电，至充电电流小于10±5mA ，停止充电。 0.5 Charge method: Under 20±5℃，65±5%RH, it can be charged to 4.2V with constant current of 350mA, and then, charged continuously with constant voltage of 4.2V until the charged current is less than 10±5mA. 2.5 1倍率充电：指在20±5℃，65±5%RH 环境下，以700mA 电流恒流充电至单体电池电压4.2V 后，转为恒压4.2V 充电，至充电电流小于10±5mA ，停止充电。 1 Charge Method: Under 20±5℃，65±5%RH, it can be charged to 4.2V with constant current of 700mA, and then, charged continuously with constant voltage of 4.2V until the charged current is less than 10±5mA. 2.6 0.2倍率放电：指在20±5℃，65±5%RH 环境下，以140mA 电流恒流放电至单体电池电压2.75V 。 0.2 Discharge Method: Under 20±5℃，65±5%RH, it can be discharged to the voltage of 2.75V with constant current of 140mA. 2.7 0.5倍率放电：指在20±5℃，65±5%RH 环境下，以350mA 电流恒流放电至单体电池电压2.75V 。 0.5 Discharge Method: Under 20±5℃，65±5%RH, it can be discharged to the voltage of 2.75V with constant current of 350mA. 2.8 1倍率放电：指在20±5℃，65±5%RH 环境下，以700mA 电流恒流放电至单体电池电压2.75V 。 1 Discharge Method: Under 20±5℃，65±5%RH, it can be discharged to the voltage of 2.75V with constant current 700mA. 3 外形尺寸 SHAPE AND PHYSICAL DIMENSION 3.1 产品的命名 Naming Instruction of Product 3EX ———— 38 34 50 AH 厂名 ———— 壳厚宽度高度特殊性能 Manufacturing Plant Diameter Length Special Property 3.2 电池尺寸 4.1+0 -0.3×33.8+0 -0.5×50.0+0 -0.5 mm 4 结构 STRUCTION 电池由正极片、负极片、隔膜、电解液、外壳等组成。 The battery consists of the positive electrode, negative electrode, separator, electrolyte and crust. 5 技术要求 TECHNICAL REQUIREMENT 5.1 使用环境 Usage Conditions 充电温度 Charging Temperature:0～45℃

锂离子电池常用的粘结剂的种类、作用及性能

锂离子电池常用的粘结剂的种类、作用及性能锂离子电池粘结剂一般都是高分子化合物，电池中常用的粘结剂有； (1)PVA(聚乙烯醇)PVA的分子式为卡CH2CHOH手JJ，聚合度”一般为700—2000，PVA是一种亲水性高聚物白色粉末，密度为1，24—1．34g?cm-3。PVA 可与其他水溶性高聚物混溶，如与淀粉、CMC、海藻钠等都有较好的混溶性。 (2)聚四氟乙烯(PTFE)PTFE俗称“塑料王”，是一种白色粉末，密度为2．1—2．3g?CITI+，热分解温度为415℃。PTFE电绝缘性能好，耐酸，耐碱，耐氧化。PTFE的分子式为卡CF2一CF2头。，是由四氟乙烯聚合而成的。nCF2＝CF、2一卡CF2＝CF2于。常用60％的PTFE乳液作电极粘结剂。 (3)羧甲基纤维素钠(CMC)CMC为白色粉末，易溶于水，并形成透明的溶液，具有良好的分散能力和结合力，并有吸水和保持水分的能力。 (4)聚烯烃类(PP，PE以及其他的共聚物)； (5)(PVDF／NMP)或其他的溶剂体系； (6)粘接性能良好的改性SBR橡胶； (7)氟化橡胶； (8)聚胺酯。锂电池用粘接剂；锂离子电池中，由于使用电导率低的有机电解液，因而要求电极的面积大，而且电池装配采用卷式结构，电池的性能的提高不仅对电极材料提出了新的要求，而且对电极制造过程中使用的粘接剂也提出了新的要求。 1、粘接剂的作用及性能； (1)保证活性物质制浆时的均匀性和安全性； (2)对活性物质颗粒间起到粘接作用； (3)将活性物质粘接在集流体上；

(4)保持活性物质间以及和集流体间的粘接作用； (5)有利于在碳材料(石墨)表面上形成SEI膜。 2、对粘接剂的性能要求； (1)在干燥和除水过程中加热到130—180~C情况下能保持热稳定性； (2)能被有机电解液所润湿； (3)具有良好的加工性能； (4)不易燃烧； (5)对电解液中的I．iClQ，I．iPP、6等以及副产物I．iOH，㈠2C03等稳定； (6)具有比较高的电子离子导电性； (7)用量少，价格低廉；以往的镍镉、镍氢电池，使用的电解液是水溶液体系，粘接剂可以使用PVA，CMC等水溶性高分子材料，或PTFE的水分散乳液。锂离子蓄电池电解液是极性大(因此溶解能力和溶胀能力高)的碳酸酯类有机溶剂体系，粘接剂必须能耐碳酸酯(至少是不溶解)，而且必须满足上述的几点要求，特别是必须满足在电化学环境中的稳定性，在负极中处于锂的负电位下不被还原，在正极中发生过充电等有氧产生的情况下不发生氧化。锂离子电池中的特点是伴随充放电过程，锂在活性物质中的嵌入—脱出引起活性物质的膨胀—收缩(如石墨的层间距变化达到10％一11％)，要求粘接剂对此能够起到缓冲作用。锂离子电池的电极在干燥过程中加热温度最高可以达到200℃，粘接剂必须能够耐受这样高的温度。由此可见，粘接剂性能好坏对电池性能的影响很大，锂离子电池电极制备是采用涂布工艺，一般采用刮刀或辊涂布的方式，通过刀口间隙调节活性物质层的厚度。锂离子电池活性物质层的厚度很小，因此涂布刀口的间隙也很小，这样就要求在浆料中不能有大的团聚颗粒存在。制作电极需要经过辊压、分

锂离子电池设计原理教材

锂离子电池原理及设计教材原理篇电池原材料化工类材料：正极：钴酸锂、锰酸锂、镍酸锂、磷酸铁锂、三元材料负极：人造石墨、中间相碳微球（沥青基）、针状焦、改性天然石墨其他：隔膜、电解液、导电剂、PVDF、NMP、草酸、SBR、CMC、高温胶纸、铜箔、铝箔等五金类材料：钢壳、铝壳、盖帽、隔圈、铝带、镍带、铝镍复合带等、铝塑膜等电池原材料是决定电池性能的最重要的因素，电池性能的提升归根结底来自于电池材料的优化及更新。锂离子电池反应机理锂离子电芯的反应机理是随着充放电的进行，锂离子在正负极之间嵌入脱出，往返穿梭电芯内部而没有金属锂的存在，因此锂离子电芯更加安全稳其反应示意图如下所示：电芯的正极是LiCoO2加导电剂和粘合剂，涂在铝箔上形成正极板，负极是层状石墨加导电剂及粘合剂涂在铜箔基带上，目前比较先进的负极层状石墨颗粒已采用纳米碳。根据上述的反应机理，正极采用LiCoO2、LiNiO2、LiMn2O2等，其中LiCoO2是一种层状结构很稳定的晶型，但当从LiCoO2拿走XLi后，其结构可能发生变化，但是否发生变化取决于X的大小。通过研究发现当X>0.5时Li(1-X)CoO2的结构表现为极其不稳定，会发生晶型瘫塌，其外部表现为电芯的电压及安全性能。所以电芯在使用过程中应通过限制充电电压来控制Li1-XCoO2中的X值，一般充电电压不大于4.2V。那么X小于0.5 ，这时Li1-XCoO2的晶型仍是稳定的。负极C6其本身有自己的特点，当第一次化成后，正极LiCoO2中的Li被充到负极C6中，当放电时Li回到正极LiCoO2中，但化成之后必须有一部分Li 留在负极C6中，以保证下次充放电Li的正常嵌入，否则电芯的寿命很短，为了保证有一部分Li留在负极C6中，一般通过限制放电下限电压来实现。所以锂电芯的安全充电上限电压≤4 .2V，放电下限电压≥2.5V。锂离子电池的主要制造过程 Li-ion电池的工艺技术比较严格、复杂，这里只能简单介绍一下其中的几个主要工序。

锂离子电池设计总结

锂离子电池设计总结（一）液锂电池设计（1）根据壳子推算卷芯 1、核算容量：（设计最低容量= average * 0.935） 2、极片宽度：隔膜宽度= 壳子高- 0.6 - 2 - 0.3 - 0.5 图纸高壳子底厚盖板厚绝缘垫厚余量负极片宽度= 隔膜纸宽度- 2mm 正极片宽度= 负极片宽度- （1~2mm）注：核算后正负极片宽度要去查找分切刀，最好有对应分切刀；箔材的选择也要依分切刀而定。比如：40mm的分切刀，可以一次分裁8片，则箔材尺寸应该为40*8+(10~15余量)=330~335mm，若没有合适的也可以选择40*7+（10~15mm）的箔材。 3、卷芯宽度：卷芯设计宽度= 壳子宽度- 0.6 -（0.5～1.5）图纸宽度两层壳壁厚余量 4、卷芯厚度：（1）卷芯设计厚度= 壳子厚度- 0.6 - 0.6 图纸厚度两层壳壁厚余量（2）卷芯设计厚度= （规格厚度–0.2 –0.6）/ 1.08 规格书厚度max 余量两层壳壁厚膨胀系数 5、卷尺宽度：卷尺= 卷芯宽–卷芯厚–卷尺厚（0.5mm）–（1.5～2.5）余量 6、最后根据（2、3、4）进行调整、确认。 7、估算卷芯/电芯最终尺寸卷芯厚度= 正极片厚+ 负极片厚+ （隔膜厚*2）卷芯宽度= 卷尺宽+ 卷尺厚+ 卷芯厚+（1～2.5）余量最终电芯厚度= 卷芯厚度* 1.08 + 壳子厚度+（0.2～0.5）层数单层厚度卷芯厚卷芯厚* 1.08 +（0.3～0.4）≤规格要求（二）电池设计注意事项： 1、极耳距极片底部≤极片宽度*1/4 2、极耳外露≥12mm~15mm 负极耳外露：6~10mm 3、小隔膜= 加垫隔膜处光泊区尺寸+（2~3mm） 4、壳子底部铝镍复合带尺寸： 4mm * 13mm * 0.1mm （当壳子底部宽w ≥7mm时） 3mm * 13mm * 0.1mm （当壳子底部宽w ＜7mm时） 5、极片称重按涂布时箔材和敷料计算

锂电池规格书

储能型磷酸铁锂电池规格书STORAGE LiFePO4 BATTERY SPECIFICATIONS 客户名称(Customer)：产品型号(Type)： CF12V80Ah 发行日期(Issuing Date)：

1. 适用范围(Product Scope) 本规格书描述了锂离子二次电池的技术要求、测量方法、运输、储存及注意事项。 This Specification describes the requirements of the lithium ion rechargeable battery supplied by 2. 电池组特性 (Battery Group Specifications)

单只电芯曲线图feature curve for single cell 3. 技术要求(Technical Requirements) 测试条件(除特别规定) Testing Conditions (unless otherwise specified) 温度Temperature: 15~35℃ 相对湿度Relative Humidity: 45%~75% 大气压Atmospheric pressure: 86~106Kpa 充放电性能 (Electrical Characteristics)

环境性能 (Environmental Characteristic) 机械性能(Mechanical characteristics)

安全性能(Safe Characteristic)

4 电池组基本性能 (Basic Characteristics of Battery) 5 电池组保护功能要求 (Battery Required Protection Functions) To insure the safety, charger and the protection circuit shall be satisfied the items below. As safety device, please use in combination with the temperature fuse. The standard charge method is CC/CV (constant current/constant voltage) 为确保安全,充电器和保护电路应符合以下要求。同时请使用装有热熔保险丝的安全装置。标准充电方法为CC/CV(恒流/恒压)

卷绕式锂离子电池设计规范

卷绕式锂离子电池设计规范一、观察给定型号和客户需求 1、型号制定了电池的尺寸（以063048为例，尺寸为6.0×30×48mm） 2、客户要求的容量和电池的放电类别（动力型、高温型、普通型），通常而言电池所能达到的容量一般为普通型＞高温型＞动力型（以便确定所需要的材料） 3、材料的选用： 3.1容量≥1000mAh的型号，如果客户无容量或高温要求的用正极CN55系列 3.2有高温要求的型号，正极材料必须使用Co系列，电解液必须用高温电解液二、卷芯设计 1、容量设计根据客户要求的最小容量来确定设计容量。设计容量（mAh）= 要求的最小容量×设计系数=（长×2-刮粉）×宽÷10000×面密度×理论克容量注：设计系数: 标称容量≤200mAh设计系数一般取1.10~1.20；标称容量200＜C≤350mAh设计系数一般取1.08±0.02；标称容量C＞350mAh设计系数一般取1.07±0.02。 2、卷针的设计 2.1 卷针的宽度 Wj=电芯的宽度-卷针厚度-电芯的厚度-1.7（根据实际情况而定） 2.2 卷针厚度 Tj由卷针的宽度决定,具体见卷针统计表。

3、包装膜尺寸设计 3.1包装膜膜腔长度的确定：膜腔长度=成品高-顶封宽度（5mm） 3.2包装膜膜腔长度的确定：膜腔宽度=成品宽-1.2mm 3.3 槽深的设计：槽深H与电芯厚度的关系如下：H = T-α 其中： T —电芯的厚度； α—当型号为双坑电池时，α取0.2 当型号为单坑电池时，α取-0.2 3.4 包装袋长、宽尺寸的确定： 3.4.1 包装袋宽度: a. 厚度≤5mm的电池铝塑膜宽度为电池本体宽度+（45～50mm），取代5mm 的整数倍为规格； b. 厚度﹥5mm的电池铝塑膜宽度为电池本体宽度+（55～60mm），取代5mm 的整数倍为规格； 3.4.2包装袋长度: 铝塑膜长度=成品电池长度×2+10mm 5、极片的设计： 5.1隔膜宽度=卷芯高度=电芯高度-5mm，（客户容量要求高的小型号电池或极片较宽的各别型号除外）；

锂离子电池的优点

锂离子电池的优点 1）能量密度高。能量密度可达460-600Wh/kg，其能量密度是铅酸电池的6-7倍； 2）相对较高的平均输出电压值。常用的锂离子电池单体平均工作电压约为3.7V，约为镍-隔电池或者镍-氢电池的3倍 3）可以高功率输出，在电动汽车的磷酸铁锂离子电池可以达到15-30C充放电能量，有利于启动加速； 4）相对较小的自放电率，无记忆效应，锂电池的自放电率为镍-隔电池或者镍-氢电池的一半甚至更小。记忆效应指的是电池在充放电循环过程中容量减小的现象，而锂离子电池在循环过程中不出现明显地容量衰减现象； 5）使用寿命长，在正常条件下，锂离子电池使用寿命可达6年，循环次数超过1000次。（6）可快速充电，使用额定电压为4.2 V的充电器只需1~2小时即可充满（7）使用温度范围宽，通常可在-30～+45℃温度范围内使用，通过调整电解液甚至可以在更宽温度范围内使用；（8）绿色电池，对环境友好，无论生产、使用和报废，都不存在镉、铅、汞等对环境有污染的元素；

Figure 4b shows the typical charge?discharge voltage profiles of the S@CNTs/Co3S4?NBs, S@Co3S4?NBs and S@CNTs electrodes at 0.2 C (1.0 C = 1,675 mAh g?1). The S@CNTs/ Co3S4?NBs electrode exhibits two typical discharge plateaus at 2.35 and 2.08 V (vs Li+/Li), originated from the reduction of S8 to soluble long-chain polysulfides (Li2Sx, 4 ≤ x ≤ 8) and the formation of insoluble short-chain polysulfides (Li2S/Li2S2), respectively. The single charge plateau of S@CNTs/Co3S4?NBs between 2.25?2.36 V is ascribed to the oxidation of Li2S/ Li2S2 to Li2Sx and eventually S8. These charge and discharge plateaus are consistent with corresponding CV curves (Figure S5). Notably, the S@CNTs/Co3S4?NBs electrode exhibits lower potential hysteresis and higher sulfur utilization ratio than those of the S@Co3S4?NBs and S@CNTs, mainly attributed to the strong chemical affinity of polar Co3S4?NBs with polysulfides and the interconnected CNT network. 图4b 显示了S@CNTs/Co3S4?NBs、S@Co3S4?NBs 和S@CNTs 电极在0.2 c (1.0 c = 1675 麻将g?1)上的典型charge?discharge 电压剖面。S@CNTs/Co3S4?NBs电极展示两个典型的放电高原在 2.35 和 2.08 V (vs li +/李), 起源于 S8 的减少到可溶性长链多硫化物 (Li2Sx, 4 ≤ x ≤ 8) 和形成不溶性短链多硫化物 (Li2S/Li2S2),分别.2.25?2.36 V 之间

锂电池项目规划设计方案

锂电池项目规划设计方案规划设计/投资方案/产业运营

锂电池项目规划设计方案说明随着电池市场规模崛起，锂电池价格还将继续下降。12月3日，彭博新能源财经(BNEF)发布锂离子电池组价格调研报告。报告显示，今年全球锂离子电池组的平均价格为156美元/千瓦时，同比下降13%;较2010年则下降87%。其中，今年中国市场锂电池组平均价格低至147美元/千瓦时，为全球最低。该锂电池项目计划总投资16251.34万元，其中：固定资产投资12110.90万元，占项目总投资的74.52%；流动资金4140.44万元，占项目总投资的25.48%。达产年营业收入38938.00万元，总成本费用31092.86万元，税金及附加314.80万元，利润总额7845.14万元，利税总额9242.03万元，税后净利润5883.86万元，达产年纳税总额3358.18万元；达产年投资利润率48.27%，投资利税率56.87%，投资回报率36.21%，全部投资回收期4.26年，提供就业职位703个。坚持“三同时”原则，项目承办单位承办的项目，认真贯彻执行国家建设项目有关消防、安全、卫生、劳动保护和环境保护管理规定、规范，积极做到：同时设计、同时施工、同时投入运行，确保各种有害物达标排放，尽量减少环境污染，提高综合利用水平。

...... 报告主要内容：项目概述、背景、必要性分析、市场调研预测、项目建设内容分析、选址评价、土建工程研究、项目工艺原则、项目环境影响分析、项目安全保护、风险评价分析、项目节能分析、实施安排、投资方案、经济收益、总结说明等。

第一章项目概述一、项目概况（一）项目名称锂电池项目随着电池市场规模崛起，锂电池价格还将继续下降。12月3日，彭博新能源财经(BNEF)发布锂离子电池组价格调研报告。报告显示，今年全球锂离子电池组的平均价格为156美元/千瓦时，同比下降13%;较2010年则下降87%。其中，今年中国市场锂电池组平均价格低至147美元/千瓦时，为全球最低。（二）项目选址某科技园（三）项目用地规模项目总用地面积46236.44平方米（折合约69.32亩）。（四）项目用地控制指标该工程规划建筑系数71.90%，建筑容积率1.52，建设区域绿化覆盖率5.55%，固定资产投资强度174.71万元/亩。（五）土建工程指标

锂电池规格书参照

聚合物锂离子电池产品规格承认书：：JD220768430F（500Ah）品名：品名编制审核批准客户确认签名//日期客户名称//印章签名客户名称总部：北京神州巨电新能源技术开发有限公司 Beijing Globe Super Power New Energy Technology Development Corp. 地址：中国北京市海淀区上地3街9号嘉华大厦E座206 ADD:Rm E-206,Gem Tech-Center,No.9,3rd Street,Haidian Dist.,Beijing,P.R.China 86-10--82783543-816Fax:86-10 86-10--82780720-1073 Tel:86-10 工厂：河北神州巨电新能源科技开发有限公司 Hebei Globe Super Power New Energy Technology Development Corp. 地址：河北邢台市巨鹿县巨鹿工业园 Hebei i Province,P.R.China ADD:Industrial District,Ju Jul l u,Xiangtan,Hebe

产品规格承认书目录 1.适用范围---------------------------------------------------------------------------------------------------------2 2.产品规格---------------------------------------------------------------------------------------------------2 3.电池性能检查测试-----------------------------------------------------------------------------------------2 4.外观尺寸图------------------------------------------------------------------------------------------------------3 5.使用指南--------------------------------------------------------------------------------------------------------3 6.其它事项------------------------------------------------------------------------------------------------------4 7.电芯处理须知---------------------------------------------------------------------------------------------------4

锂离子电池工作原理

锂离子电池工作原理正极反应：放电时锂离子嵌入，充电时锂离子脱嵌。负极反应：放电时锂离子脱插，充电时锂离子插入。电池总反应以炭材料为负极，以含锂的化合物作正极的锂电池，在充放电过程中，没有金属锂存在，只有锂离子，这就是锂离子电池。当对电池进行充电时，电池的正极上有锂离子生成，生成的锂离子经过电解液运动到负极。而作为负极的碳呈层状结构，它有很多微孔，达到负极的锂离子就嵌入到碳层的微孔中，嵌入的锂离子越多，充电容量越高。同样，当对电池进行放电时（即我们使用电池的过程），嵌在负极碳层中的锂离子脱出，又运动回正极。回正极的锂离子越多，放电容量越高。我们通常所说的电池容量指的就是放电容量。在Li-ion的充放电过程中，锂离子处于从正极→负极→正极的运动状态。Li-ion Batteries就像一把摇椅，摇椅的两端为电池的两极，而锂离子就象运动员一样在摇椅来回奔跑。所以Li-ion Batteries又叫摇椅式电池。一般锂电池充电电流设定在0.2C至1C之间，电流越大，充电越快，同时电池发热也越大。而且，过大的电流充电，容量不够满，因为电池内部的电化学反应需要时间。就跟倒啤酒一样，倒太快的话会产生泡沫，反而不满。正极正极材料：可选正极材料很多，目前主流产品多采用锂铁磷酸盐。正极反应：放电时锂离子嵌入，充电时锂离子脱嵌。充电时：LiFePO?→ Li1-xFePO? + xLi + xe

放电时：Li1-xFePO?+ xLi + xe →LiFePO? 负极负极材料：多采用石墨。新的研究发现钛酸盐可能是更好的材料。负极反应：放电时锂离子脱插，充电时锂离子插入。充电时：xLi + xe + 6C →LixC6 放电时：LixC6 → xLi + xe + 6C 锂离子电池是一种二次电池（充电电池），它主要依靠锂离子在正极和负极之间移动来工作。在充放电过程中，Li+ 在两个电极之间往返嵌入和脱嵌：充电池时，Li+从正极脱嵌，经过电解质嵌入负极，负极处于富锂状态；放电时则相反。电池一般采用含有锂元素的材料作为电极，是现代高性能电池的代表。组成部分钢壳/铝壳/圆柱/软包装系列：（1）正极——活性物质一般为锰酸锂或者钴酸锂，镍钴锰酸锂材料，电动自行车则普遍用镍钴锰酸锂（俗称三元）或者三元+少量锰酸锂，纯的锰酸锂和磷酸铁锂则由于体积大、性能不好或成本高而逐渐淡出。导电集流体使用厚度10--20微米的电解铝箔。（2）隔膜——一种经特殊成型的高分子薄膜，薄膜有微孔结构，可以让锂离子自由通过，而电子不能通过。（3）负极——活性物质为石墨，或近似石墨结构的碳，导电集流体使用厚度7-15微米的电解铜箔。

储能电站总体技术方案设计

储能电站总体技术方案 2011-12-20

目录 1.概述 (3) 2.设计标准 (4) 3.储能电站（配合光伏并网发电）方案 (6) 3.1系统架构 (6) 3.2光伏发电子系统 (7) 3.3储能子系统 (7) 3.3.1储能电池组 (8) 3.3.2 电池管理系统(BMS) (9) 3.4并网控制子系统 (12) 3.5储能电站联合控制调度子系统 (14) 4.储能电站（系统）整体发展前景 (16)

1.概述大容量电池储能系统在电力系统中的应用已有20多年的历史，早期主要用于孤立电网的调频、热备用、调压和备份等。电池储能系统在新能源并网中的应用，国外也已开展了一定的研究。上世纪90年代末德国在Herne 1MW的光伏电站和Bocholt 2MW的风电场分别配置了容量为1.2MWh的电池储能系统，提供削峰、不中断供电和改善电能质量功能。从2003年开始，日本在Hokkaido 30.6MW 风电场安装了6MW /6MWh 的全钒液流电池（VRB）储能系统，用于平抑输出功率波动。2009年英国EDF电网将600kW/200kWh锂离子电池储能系统配置在东部一个11KV配电网STATCOM中，用于潮流和电压控制，有功和无功控制。总体来说，储能电站（系统）在电网中的应用目的主要考虑“负荷调节、配合新能源接入、弥补线损、功率补偿、提高电能质量、孤网运行、削峰填谷”等几大功能应用。比如：削峰填谷，改善电网运行曲线，通俗一点解释，储能电站就像一个储电银行，可以把用电低谷期富余的电储存起来，在用电高峰的时候再拿出来用，这样就减少了电能的浪费；此外储能电站还能减少线损，增加线路和设备使用寿命；优化系统电源布局，改善电能质量。而储能电站的绿色优势则主要体现在：科学安全，建设周期短；绿色环保，促进环境友好；集约用地，减少资源消耗等方面。

锂离子电池基础知识-锂离子电池型号命名规则

锂离子电池基础知识 ——锂离子电池型号命名规则根据IEC61960标准二次锂电池的标识如下： 1.电池标识组成 a)圆柱形二次锂离子的表示方法为：3个字母+5个数字； b)方形二次锂离子的表示方法为：3个字母+6个数字。 2.第一个字母表示电池的负极材料 a)I表示锂离子电池； b)L表示锂金属电极或锂合金电极。 3.第二个字母表示电池的正极材料 a)C是基于钴的电极； b)N是基于镍的电极； c)M是基于锰的电极； d)V是基于钒的电极。 4.第三个字母表示电池的形状 a)R表示圆柱形电池； b)L表示方形电池。 5.圆柱形电池5个数字分别表示电池的直径和高度， a)字母后前两个数字表示电池的直径，单位为mm； b)后两个数字表示电池的高度的十倍，单位为mm； c)直径或高度任一尺寸大于或等于100mm时两个尺寸之间应加一条斜线。 6.方形电池6个数字分别表示电池的厚度、宽度和高度 a)前两个数字表示电池的厚度，单位为mm； b)中间两个数字表示电池的宽度，单位为mm； c)后两个数字表示电池的高度，单位为mm； d)厚度、宽度和高度三个尺寸任一个大于或等于100mm时尺寸之间应加斜线，三个尺寸中若有任一小于1mm，则在此尺寸前加字母t，此尺寸单位为十分之一毫米。

例如： ICR18650表示一个圆柱形二次锂离子电池，正极材料为钴，其直径约为18mm，高约为65mm； ICR20/1050 表示一个圆柱形二次锂离子电池，正极材料为钴，其直径约为20mm，高约为1050mm； ICP083448表示一个方形二次锂离子电池正极材料为钴其厚度约为8mm，宽度约为34mm，高约为48mm； ICP08/34/150表示一个方形二次锂离子电池正极材料为钴其厚度约为8mm，宽度约为34mm，高约为150mm； ICPt073448表示一个方形二次锂离子电池正极材料为钴其厚度约为0.7mm，宽度约为34mm，高约为48mm。型号后面的字母表示材质，例如方形锂离子电池（厚度\宽度\高度\材质），063048S型号代表厚度为6mm，宽度为30 mm，高度为48 mm，S代表钢壳，A代表铝壳。

锂离子电池简介及主要应用

锂离子电池简介使用煤炭，石油和天然气的很长一段时间以来，都是以化石燃料为主要能源，这样的能源结构，使得环境污染严重，并且由此导致的全球变暖问题和生态环境恶化问题受到越来越多的关注。所以，可再生能源和新能源的发展成为在未来技术领域和未来经济世界的一个最具有决定性的影响。锂离子电池作为一种新的二次清洁，且可再生能源，其具有工作电压高，质量轻，能量密度大等优点，在电动工具，数码相机，手机，笔记本电脑等领域得到了广泛的应用，并且显示出强大的发展趋势。锂离子电池的发展历史第二十世纪六十、七十年代，几乎在锂电池是发明的同时，研究发现许多插层化合物可以与金属锂的可逆反应，构成锂电池[1]。早在第二十世纪七十年代提出了分层组织作为阴极的斯梯尔最有代表性的一种，金属锂作为阳极的Li-TiS2系统。 1976年Whittingham证实了系统的可靠性。随后，埃克森公司的Li-TiS2系统进行深入研究，并希望其商业化。但是，系统很快就暴露出许多致命的缺陷。首先，活性金属锂容易导致有机电解液的分解，导致电池内部压力。由于锂电极表面的表面电位分布不均匀，在锂金属的电荷将在锂沉积的阴极，产生锂“枝晶”。一方面会造成可逆嵌锂容量损失，另一方面，枝晶可以穿透隔膜和负极连接，造成电池内部短路，瞬间吸收大量的热，发生爆炸，导致严重的安全隐患。这一系列因素导致金属锂电池的循环性能和安全两差异，所以Li-TiS2系统未能实现商业化。 1980，阿尔芒首次提出摇椅电池的想法。使用低锂嵌入化合物锂化合物代替金属锂作为阳极，采用高嵌锂电位嵌锂化合物作正极。同年，在美国德州大学Goodenough教授的国家提出了一系列的锂过渡金属氧化物LixMO2（M=Co 、Ni 或Mn)为两电池正极材料锂。1987，奥邦成功组装了浓差电池MO2 (WO2)/LiPF6-PC/LiCoO2和证明“摇椅电池”的想法的可行性，但由于负电极材料形成LiMoO2 CLiWO2嵌入电位高(0.7-2.0 V vs.Li/Li+)嵌锂容量较低，并没有显示高电压的锂离子二次电池的优点，比容量高。

锂电池保护电路设计方案

锂电池保护电路设计方案锂电池材料构成及性能探析首先我们来了解一下锂电池的材料构成，锂离子电池的性能主要取决于所用电池内部材料的结构和性能。这些电池内部材料包括负极材料、电解质、隔膜和正极材料等。其中正、负极材料的选择和质量直接决定锂离子电池的性能与价格。因此廉价、高性能的正、负极材料的研究一直是锂离子电池行业发展的重点。负极材料一般选用碳材料，目前的发展比较成熟。而正极材料的开发已经成为制约锂离子电池性能进一步提高、价格进一步降低的重要因素。在目前的商业化生产的锂离子电池中，正极材料的成本大约占整个电池成本的40%左右，正极材料价格的降低直接决定着锂离子电池价格的降低。对锂离子动力电池尤其如此。比如一块手机用的小型锂离子电池大约只需要5克左右的正极材料，而驱动一辆公共汽车用的锂离子动力电池可能需要高达500千克的正极材料。尽管从理论上能够用作锂离子电池正极材料种类很多，常见的正极材料主要成分为LiCoO2，充电时，加在电池两极的电势迫使正极的化合物释出锂离子，嵌入负极分子排列呈片层结构的碳中。放电时，锂离子则从片层结构的碳中析出，重新和正极的化合物结合。锂离子的移动产生了电流。这就是锂电池工作的原理。锂电池充放电管理设计锂电池充电时，加在电池两极的电势迫使正极的化合物释出锂离子，嵌入负极分子排列呈片层结构的碳中。放电时，锂离子则从片层结构的碳中析出，重新和正极的化合物结合。锂离子的移动产生了电流。原理虽然很简单，然而在实际的工业生产中，需要考虑的实际问题要多得多：正极的材料需要添加剂来保持多次充放的活性，负极的材料需要在分子结构级去设计以容纳更多的锂离子;填充在正负极之间的电解液，除了保持稳定，还需要具有良好导电性，减小电池内阻。虽然锂离子电池有以上所说的种种优点，但它对保护电路的要求比较高，在使用过程中应严格避免出现过充电、过放电现象，放电电流也不宜过大，一般而言，放电速率不应大于0.2C。锂电池的充电过程如图所示。在一个充电周期内，锂离子电池在充电开始之前需要检测电池的电压和温度，判断是否可充。如果电池电压或温度超出制造商允许的范围，则禁止充电。允许充电的电压范围是：每节电池2.5V~4.2V。

钛酸锂系列锂离子电池相关参数

钛酸锂系列锂离子电池相关参数 IMB standardization office【IMB 5AB- IMBK 08- IMB 2C】

钛酸锂系列锂离子电池相关参数一、钛酸锂电池的概述作为锂离子电池负极材料-钛酸锂，可与锰酸锂、三元材料或磷酸铁锂等正极材料组成 V或的锂离子二次电池.此外，它还可以用作正极，与金属锂或锂合金负极组成 V的锂二次电池。由于钛酸锂的高安全性、高稳定性、长寿命和绿色环保的特点。可以预见：钛酸锂材料在2－3年后，一定会成为新一代锂离子电池的负极材料而被广泛应用在新能源汽车、观光车、电动自行车摩托车和要求高安全性、高稳定性和长周期储能等电池的应用领域。二、单体电池的特点 1、独立单电池对流散热结构，能更有效低避免过热相互影响； 2、单电池独立定位支点结构，能有效防止电池在振动环境产生串动，避免了串动的摩擦破坏电池外层绝缘隔离，避免累积性的挤压效应，消除了相互挤压造成电池内部受挤压损坏电池隔膜造成危险。三、单体电池技术参数

四、电池组模块技术参数五、电池组模块结构特点： 1. 无框架连接固定结构，有效提高体积比能量密度； 2. 联接电极防水结构，能有效改善导电接触点氧化产生的接触电阻； 3. 弹性补偿抗震串联接电结构，能防止震动环境造成的接触不良； 4. 非焊接引线结构，能避免焊接高温产生对极耳电极密封破坏； 5. 内压恒压结构，保持电池稳定内压，更好的避免粘合处、密封绝缘隔离处受到水分渗入。碳负极锂离子电池的缺点：采用电动车辆取代燃油车辆是解决城市环境污染的最佳选择，其中锂离子动力电池引起了研究者的广泛关注.为了满足电动车辆对车载铿离子动力电池的要求，研制安全性高、倍率性能好且长寿命的负极材料是其热点和难点。目前，商业化的锂离子电池负极主要采用碳材料，但以碳做负极的锂电池在应用上仍存在一些弊端： 1、过充电时易析出锂枝晶，造成电池短路，影响锂电池的安全性能; 2、易形成SEI膜而导致首次充放电效率较低，不可逆容量较大; 3、即碳材料的平台电压较低(接近于金属锂)，并且容易引起电解液的分解,从而带来安全隐患。 4、在锂离子嵌入、脱出过程中体积变化较大，循环稳定性差。六、相比传统材料，钛酸锂负极的明显优势

锂离子电池原理及生产工艺流程

锂离子电池原理及工艺流程一、原理 1.0 正极构造 LiCoO2(钴酸锂)+导电剂+粘合剂(PVDF)+集流体（铝箔）正极2.0 负极构造石墨+导电剂+增稠剂(CMC)+粘结剂(SBR)+ 集流体（铜箔）负极3.0工作原理 3.1 充电过程：一个电源给电池充电,此时正极上的电子e从通过外部电路跑到负极上,正锂离子Li+从正极“跳进”电解液里，“爬过”隔膜上弯弯曲曲的小洞，“游泳”到达负极，与早就跑过来的电子结合在一起。正极上发生的反应为 LiCoO2=充电=Li1-xCoO2+Xli++Xe(电子) 负极上发生的反应为 6C+XLi++Xe=====LixC6 3.2 电池放电过程放电有恒流放电和恒阻放电，恒流放电其实是在外电路加一个可以随电压变化而变化的可变电阻，恒阻放电的实质都是在电池正负极加一个电阻让电子通过。由此可知，只要负极上的电子不能从负极跑到正极，电池就不会放电。电子和Li+都是同时行动的，方向相同但路不同，放电时，电子从负极经过电子导体跑到正极，锂离子Li+从负极“跳进”电解液里，“爬过”隔膜上弯弯曲曲的小洞，“游泳”到达正极，与早就跑过来的电子结合在一起。二工艺流程

1.正负极配方 1.1正极配方（LiCoO2(钴酸锂)+导电剂(乙炔黑)+粘合剂(PVDF)+集流体（铝箔）正极） (10μm):93.5% LiCoO 2 其它：6.5% 如Super-P:4.0% PVDF761:2.5% NMP（增加粘结性）:固体物质的重量比约为810:1496 a)正极黏度控制6000cps(温度25转子3)； b)NMP重量须适当调节，达到黏度要求为宜； c)特别注意温度湿度对黏度的影响 ●钴酸锂：正极活性物质，锂离子源，为电池提高锂源。钴酸锂：非极性物质，不规则形状，粒径D50一般为6-8 μm，含水量≤0.2%，通常为碱性，PH值为10-11左右。锰酸锂：非极性物质，不规则形状，粒径D50一般为5-7 μm，含水量≤0.2%，通常为弱碱性，PH值为8左右。 ●导电剂：提高正极片的导电性，补偿正极活性物质的电子导电性。提高正极片的电解液的吸液量，增加反应界面，减少极化。非极性物质，葡萄链状物，含水量3-6%，吸油值~300，粒径一般为2-5 μm；主要有普通碳黑、超导碳黑、石墨乳等，在大批量应用时一般选择超导碳黑和石墨乳复配；通常为中性。 ●PVDF粘合剂：将钴酸锂、导电剂和铝箔或铝网粘合在一起。非极性物质，链状物，分子量从300，000到3，000，000不等；吸水后分子量下降，粘性变差。 ●NMP：弱极性液体，用来溶解/溶胀PVDF，同时用来稀释浆料。 ●正极引线：由铝箔或铝带制成。 1.2负极配方（石墨+导电剂(乙炔黑)+增稠剂(CMC)+粘结剂(SBR)+ 集流体（铜箔）负极）负极材料：94.5% Super-P:1.0% SBR:2.25% CMC:2.25% 水：固体物质的重量比为1600:1417.5