Rechargable Batteries

[SEK_22Hornet]

I rebuilt a hand held transceiver battery pack using 3 LI Ion cells and a protection board from ebay (runs around 10.5 to 12 volts). The board controls charging max voltage, max discharge rate, and low voltage cut-off. It was less than $6 if i remember and the pack works great! No worries about the cells since it is designed to monitor all cells individually (cells all wire to points on the board). No special charger required - the board cuts off the charge when the max cell voltage is reached. I still have some cells and are thinking about a Li Ion battery for my olde Ryobi 12 volt drill. Still have a couple boards left

 

[DAN_IN_MN]

I rebuilt a hand held transceiver battery pack using 3 LI Ion cells and a protection board from ebay (runs around 10.5 to 12 volts). The board controls charging max voltage, max discharge rate, and low voltage cut-off. It was less than $6 if i remember and the pack works great! No worries about the cells since it is designed to monitor all cells individually (cells all wire to points on the board). No special charger required - the board cuts off the charge when the max cell voltage is reached. I still have some cells and are thinking about a Li Ion battery for my olde Ryobi 12 volt drill. Still have a couple boards left

Great post, Dan from Kansas!

 

[mattthemuppet2]

those PCBs are great, but you have to make sure that all the series cells are very similar (same batch ideally) and at the exact same state of charge when you wire the pack up as they won't balance the cells. They will cut off the pack when it goes too far out of balance though. Balance charging PCBs (which you'll see in li-ion tool packs) are much larger and more expensive.

The 5S PCBs I found (not even balance charging ones) were crazy expensive, otherwise I would have used one along with the balance tap. As it is, some care and attention should be fine.