Test/review of iPowerUS 9V Pro 520mAh (Silver)

Batteries and Chargers Rechargeable Batteries
1

iPowerUS 9V Pro 520mAh (Silver)







Official specifications:

  • Dimensions: 25.5mm x 16.4mm x 47.5mm

  • Nominal capacity: 520mAh / Minium capacity: 500mAh

  • Charging voltage: 8.4V ± 0.05V

  • Nominal discharging current: up to 500mA

  • Nominal voltage: 8.4V ~ 6.5V / Working voltage: 8.4V - 6.5V

  • Discharge end voltage: 6.5V

  • Storage temperature (in centigrade): 0 - 40 degrees

  • Charge temperature: 0 - 40 degrees

  • Discharge temperaure: 10 45 degrees

  • Over voltage protect: 8.50V ± 0.05V

  • Low voltage protect: 6.5V (+0.2V/-0.4V)

  • Internal resistance: <=450mOhm




This is a two cell LiIon rechargeable battery.
I skipped making the 0.002 and 0.005A curves, they will not be significantly different from the 0.01A curve.
This type of batteries are equipmped with a LiIon protection circuit. I tested one of the batteries it had over voltage protection at 8.35V and over discharge protection at 6.22V












The two batteries has slightly different capacity, but the actual capacity do not change much with load.
The voltage is lower than NiMH and more like a nearly empty alkaline, but it will stay this way for a very long time.











Conclusion

These batteries have more than double capacity compared to NiMH 9V batteries and are close to a alkaline battery at low load, except this battery will maintain high capacity at high load.

In moderate to high load situations this looks like a good replacement for alkaline.



Notes and links

How is the test done and how to read the charts
Compare to other 9V batteries: Alkaline/NiMH/Lithium
2

Thanks for the test!
I have read about another brand of 2S LiPo dying early because of lack of an internal balancing circuit (could be a BQ29200). I would not buy such a battery unless I was sure that it has balancing. I hope you can provide that information in future tests.
Do you have the ZNTER 9V battery (9.5V) in queue?. It is a 2P LiPo with output booster and therefore does not need balancing. I have a few of those and also some Soshine 650mAh (2S=7.4V) that I would like to know the quality of.

3

Checking for a balancing circuit would require opening the battery. I doubt it has balancing circuit, when I check 2S packs they are always without.

I am working on the ZNTER.

4

Great!
If you do not open the ZENTER, I can add a (nice) photo of the circuit board with charger, protection and booster-IC’s. It was easy to open with 2 screws under the wrap.

5

I was not planning on opening it in the review, but I hope at a later date to open a couple of 9V batteries.

You are welcome to add your picture to my review when I publish it.

6

Could you post these photos ? Hopefuly IC symbols are readable.

Is there really a protection circuit inside?