1C Continual Discharge: ≥80%

(100% DOD)

Pole torsion

Criteria

4.1 High

Temperature

Discharge Performance

Capacity retention at 55℃

:≥95%

4.2 Low

Temperature

Discharge

Performance

Capacity retention at -20℃

:≥70%

A cell is charged in accordance with 3.2, and stored in certain ambient temperature for 24hours,then discharged to cut-off voltage(1.8V) at a constant current of 1C. After that , fetch out the cell and place it in the ambient temperature of 25℃±5℃for 4hours.

4.3

Rate Charge Performance

in Normal Temperature

2C charge capacity≥80%

Under the ambient temperature of 25℃±5℃,

a, 1C constant discharge till the cut-off voltage, standby for 1h;

b, charge at certain current till 3.65V, standby for 1h;

c, constant discharge with 1C current till 2.0V.

4.4

Rate Discharge Performance in Normal Temperature

3C discharge capacity≥95%

A cell is charged in accordance with 3.2, then discharged to cut-off voltage at certain current in an ambient temperature of 25℃±5℃.

4.5 Cycle Life

(25℃±5℃)

A cell is 1C CC/CV 3.65V fully charged, after that stored for 30min; Subsequently, the cell is discharged to cut-off voltage at a constant current of 1C, and stored 30min prior to next charge-discharge cycle, until the capacity retention＜80%, and record all the cycles

Test Method

Criteria

A cell is charged in accordance with 3.2, and then repeat the following procedures for 5 cycles, then check the cell's appearance.

Low-pressure

Test

A cell is charged in accordance with 3.2, then stored for 6h at a vacuum of -90KPa, after that put the cell in room temperature for 6h, then check the cell's appearance.

A cell is charged in accordance with 3.2, and then installed onto the vibration desk with clamps. Equipment parameters of frequency and amplitude are set as bellow (the frequency is to be varied at the rate of 1oct/min between 10 and 55 Hz, and repeat vibration for 30 min. The cell is tested in three mutually perpendicular directions, i.e. X,Y,Z):

(a) frequency:10Hz~30Hz, amplitude: 0.38mm;

(b) frequency:30Hz~55Hz amplitude: 0.19mm

1.No scratch, no fire, no explosion, no vent;

2.The voltage is not less than 3.2V.

Shock Test

A cell is tested in accordance with 3.2, and then secured to the testing machine by means of rigid mount which supports all mounting surfaces of the cell. Each cell shall be subjected to a total of three shocks of equal magnitude. The shocks are to be applied in each of three mutually perpendicular directions. The acceleration and impulse time are as follows: acceleration of impulse peak value:100m/s², shock frequency:40~80 times/min,

impulse lasting time:16 min,shock times:1000±10

1.No scratch, no leakage, no fire, no explosion, no vent;

2.the voltage is not less than 3.2V.

Test Method

Criteria

Overcharge

Test

No fire, no explosion

Impact Test

nail penetration Test

a) A cell is tested in accordance with 3.2;

b) use φ5mm～φ8mm high temperature resistance steel needle, with speed of 25±5mm/s, to go through the cell from vertical direction of pole plate, the penetrate position should be close to the geometric center of plate surface, the steel needle remains in the cell;

c)observe for 1h.

Heating

Test(130℃)