Electrical – Charging batteries and how voltage affects it

batteriesbattery-charging

I know that when I am charging a battery, we need higher voltage than the battery is rated at in order to "push" current into the battery itself. Right? OK. Since that is true, is it possible for me to use a lower voltage, but into the separate battery packs? I WILL EXPLAIN. I am sending current into a 10 volt light bulb. The batteries I am using to send that current are eight 1.2V rechargeable aaa batteries (NI-MH) put into series. BUT I am using 3 battery holders, 2 of them hold 3 batteries, and one holds 2 batteries, as shown on the following pictures. So basically these battery holders are put into series. Now, when I charge them, how is the voltage distributed amongst all 8 batteries? Like, is the 5 volts going to go to each battery holder charging them individually, even thought they are in series? Is there a way I can charge this battery pack with 5 volts? enter image description here
If this doesnt work, how about this?: enter image description here Will each aaa battery get 5 volts, or each battery pack get 5 volts, or my whole setup get 5 volts? The reason I am asking this is because I know that in order to charge a battery you need higher voltage than it gives out, and a diode won't solve my problem of my setup won't work.

Best Answer

You could merge the two sets of 3 batteries and charge them in series with 7.2v (assuming they're balanced) but the pack of 2 batteries needs to be charged separately with a source of 2.4v.

Nevertheless, if you could remove the batteries it would be extremely recommended to charge each cell separately so they will be balanced and the risk of corrosion will be practically zero.