9V Rechargeable Question

[icebird144]

Not sure if this is the right place to post, since I don't think people use 9V battery on flashlights

But recently I've bought a Maha MH-C490F 9V rechargeable charger with 3 batteries (it claims it will give 9.6V when fully charged). However, when I finished charging and use a multimeter to test the voltage, it's showing up at almost 11V, and the batteries themselves are warm/very warm.

Does anyone know if this is normal? Or is there a fault in the charger (I think the batteries are ok since they are new, and the problem happens to all 3 of them)

Thanks!

 

[45/70]

Welcome to CPF icebird144! :thumbsup:

Yes this is the correct section, and yes 11+ Volts is normal for an 8 cell, 9 Volt NiMH battery that is fully charged.

9.6 Volts is the nominal rating, meaning under load. NiMH (and NiCd) cells have a 1.2 Volt nominal rating, whereas their actual open circuit voltage when fully charged is somewhere close to 1.4 Volts. So anyway, a 9.6 volt battery has 8 small NiMH cells inside it (usually AAAA) so we have 8x1.2=9.6 (nominal voltage) or, 8x1.4=11.2 (open circuit voltage).

Dave

 

[tabetha]

As said exactly what I found as well.
tabetha