5
INR 18650 35 E
Cylindrical Lithium Ion Cell
TerraE Confidential Proprietary and not be reproduced without written permission from BMZ Germany GmbH, Zeche Gustav 1, 63791 Karlstein
7.3 INTERNAL IMPEDANCE
7.4 DISCHARGE RATE CHARACTERISTICS
The impedance shall be measured by 6.1.2
Initial Internal Impedance ≤
4
5mΩ
Cells shall be charged per 7.1.1 (0.2C) at 25°C and dischar-
ged per 7.2.1(0.2C), 7.2.2 (0.5C), 7.2.3 (1C), 7.2.4 (2C) at 25°C.
The discharge capacity of each cell at respective dischar-
ge rate shall be compared with the discharge capacity at
0.2C and the percentage shall be calculated. Each cell shall
meet or exceed the requirements of Table 1.
Table 1:
DISCHARGE CURRENT
AVAILABLE CAPACITY
0.2C
100%
1.0
C
≥95%
2
.0C
≥93%
3
.0C
≥90%
7.5 CYCLE DEFINITION
Charge cells per 7.1.2. Rest 15 minutes. Discharge per 7.2.3. Rest 15 minutes before recharge. The test environmental
temperature is 25°C ±
2
°C. A cycle is defined as one charge and one discharge. Discharge capacity shall be measured
after
8
00 cycles.
Discharge capacity (500th Cycle) ≥
8
0% of 1st Cycle Capacity
7.6 STORAGE CHARACTERISTICS
7.6.1
After charge as per 7.1.1, store the testing cells at 25°C ±
2
°C for 28 days. Then discharge as per 7.2.2. Then the same
cell is fully charged as per 7.1.1 again and discharged a second time and measured as per 7.2.2.
The recovery discharge capacity (2nd discharge capacity) ≥90% of initial capacity.
7.6.2
After charge as per 7.1.1, store the testing cells at 55°C ± 3°C for 7 days. Then discharge as per 7.2.2. Then the same
cell is fully charged as per 7.1.1 again and discharged a second time and measured as per 7.2.2.
The recovery discharge capacity (2nd discharge capacity) ≥90% of initial capacity.
7.7 TEMPERATURE CHARACTERISTICS
Cells shall be charged per 7.1.1 and discharged per 7.2.3. Cells , fully charged, shall be stored for 3 hours at the test
temperature .The capacity of a cell at each temperature shall be compared to the capacity achieved at 25°C and the
percentage shall be calculated. Each cell shall meet or exceed the requirements of Table 2.
Table 2:
TEMPERATURE
AVAILABLE CAPACITY
-
2
0°C
≥70%
0°C
≥80%
25°C
100%
45°C
≥
100
%
60
°C
≥100
%
7.2 DISCHARGE METHOD
7.2.1
Cells shall be discharged at a constant current of 0.2C to 2.5 volts
7.2.2
Cells shall be discharged at a constant current of 0.5C to 2.5 volts
7.2.3
Cells shall be discharged at a constant current of 1.0C to 2.5 volts
7.2.4
Cells shall be discharged at a constant current of 2.0C to 2.5 volts
