dacaur
Posts: 863
Joined: 4/18/2005 From: midvale,
UT, USA Status: online
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quote:
ORIGINAL: BigTb17 I read somewhere in this thread that you shouldn't use the lithium setting on a Triton Jr. or similar to charge A123 batteries because they are only 3.3 volts per cell (the lithium setting on the Triton Jr. is 3.6 volts per cell). However, I have a power tool pack which has 3 A123 cells inside and it is labeled 10.8 volts which would indicate 3.6 v per cell. Am I missing something? Is there any reason I couldn't charge those cells with my Triton Jr.? If not, what is different about the A123 setting on other chargers? Edit: Ok, now I'm seriously confused. I just tested the voltage of the pack to see what it read and it is 11.27v . Very strange. I may just keep using them as power tool packs . By the way, it is not a VPX, it is a Bosch Pocket Impactor. It is their Litheon 10.8 volt pack and it has three cells labeled 18650, which according to A123 Support is the part number of their 1100 mAh cell. So my assumption was that they were the same or similar. Bosch's claims on their site definitely suggest they use A123 cells. Though maybe they use something different. Here is the problem, A123's are odd in that they are marketed at their full charge voltage, which is 3.6v, rather than their "nominal" voltage of 3.3v... so a 3 cell pack will be marketed at 10.8v, which is its fully charged voltage, while a 3 cell lipo is marketed at 11.1v, which is its mostly discharged, or "Nominal" voltage... A fully charged lipo cell is actualy 4.2v.... so a 3 cell lipo fully charged will be 12.6v... 3.7v is a lipo's "nominal" voltage, which is the resting voltage at which is is mostly discharged. All other rechargeable batteries are also marketed at their "nominal" voltage. A nicad/nimh is said to be 1.2v, though fully charged its 1.45v, and almost dead at 1.2... So basically, a 3 cell A123 pack is fully charged at 10.8v, but your triton JR will want to charge it to 12.6v.... see the problem?
< Message edited by dacaur -- 6/26/2008 11:40:48 PM >
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