Vapcell IMR26650 4600mAh (Yellow)



Official specifications:

• Product: Vacell 26650 4600mAh
• Model: IMR 26650
• Size: 26.2*65.2mm
• Nominal voltage: 3.6V
• Charge voltage: 4.2V
• Max. charge voltage: 4.25V
• Typical Capacity: 4600mAh (0.2C discharge)
• Min capacity: 4500mAh (0.2C discharge)
• top: Flat top
• color: yellow
• weight: 98g max
• Internal Resistance: <20mOhm
• Standard Charge: 1.5A, 4.20 ± 0.05 V, CCCV 100mA cut-off
• Continuous maximum charge current: 4A
• discharge cut-off voltage: 2.5v
• Continuous maximum discharge current: 40A
• Max Discharging Current: 60A
• Operating environment: Charging, 0°C ~ 45°C, Discharging, -20°C~75°C
• Storage environment: -30°C~55°C, storage >3 months: -20°C~45°C

A high current and high capacity 26650 cell.










The last pictures shows the batteries after the test, obvious they vented.



The two cells has different capacity and cannot really deliver 30A (The huge dive at the start of the yellow curve shows that the batteries cannot deliver 30A, before they are heated up). 20A would be a more realistic rating for them.















Conclusion

I do not like when batteries have different capacity and with unprotected cells it is very important not to use them in series.
The current rating is also very much on the optimistic side and the venting at less than rated current confirms this.



Notes and links

The batteries was supplied by Vapcell for review.

How is the test done and how to read the charts
How is a protected LiIon battery constructed
More about button top and flat top batteries
Compare to 18650 and other batteries