Lithium battery PCM question

Discussion in 'The Projects Forum' started by chimera, Apr 21, 2012.

  1. chimera

    Thread Starter Member

    Oct 21, 2010
    Hello. I have a question regarding the PCM of a single lithium cell. PCM stands for 'protection control module'.

    It basically sets the charge and discharge, over-voltage and under-voltage limits for the cell. Basically, its tiny piece of pcb that is connected the to the tabs of the cell.

    Now, by default, I can CONTINUOUSLY discharge the battery @ 0.2C. This means that if my battery is 2400mAh, then i can only continuously discharge it at ≈ 490mA. However, i have seen on the data sheets of some of these PCMs that there is MAXIMUM CONTINUOUS discharge current of like 1C or something like that.

    How do I configure my present PCM to discharge at 1C. The issue around this problem is that the IC name on the PCM board have been erased so I cant look up the IC and then work around that. However, a good bit of researching brought me a typical IC that's does the whole protection: S-8261 by Seiko. That's right!!! SEIKO!!! did not see that coming.

    I cant go for a bigger size of the battery caz I have pcb real estate limitation. The only alternative I have is to use a bigger discharge rate.So does anyone think they can help me at this?? All help is much appreciated.
    Last edited: Apr 21, 2012