m6500 cmos battery questions

Hello, I recently purchased this m6500, the main battery is hardly holding a charge if at all, shows 29% always. I had some trouble booting into an iso disc linux image, I believe I was able to do it by going into the BIOS and manually resetting the clock [off by years]. Anyway, there are other problems maybe for another thread but right now, with it plugged in, I booted into BIOS and the clock keeps falling back to 2013, which I think might be causing boot problems to iso. Would the clock resetting indicate the cmos battery is toast?

If it is, anyone have success soldering a new one into the holder? If not I'd have to wait for a harnessed one to come from ebay, would like to proceed asap. thanks

 

Yes, clock reset is a good sign that the CMOS battery is bad.
Seems likely that Dell has been using the same battery connector for a good while so one from a newer system might work. (I'm not sure about the M6500 in particular; all of my systems are newer than that.) In any case, there are companies selling new compatible replacement batteries (i.e. https://www.amazon.com/dp/B076V27XJ5)

 

thanks! I'll have to get back to this later, and research possibilities of soldering in a battery I have on hand to the harness, don't want to wait but at least I have my other m6500 already up and running.

 

I found a good tute on youtube for fitting a raw battery into the harness [do not solder!]. I had all the parts on hand but unfortunately the little white plastic connector on the end of the 3 wires disintegrated as I was removing it. Happy to have found a seller on ebay as the one on Amazon projected arriving June/July! Delays due to corona virus, I assume. Ebay was cheaper as well.
tutorial:

ebay m6400/m6500 rtc batteries. I bought 2 because not only do I have another m6500 but didn't want to get caught short again on the connector breaking:
https://www.ebay.com/itm/New-Assemb...375371?hash=item34072836cb:g:O8sAAOSwKVVbL0gV