Thinkpads Forum

Is there a way to verify if it's completely dead? Can I try and clear the battery and recharge?

guest user wrote:Is there a way to verify if it's completely dead? Can I try and clear the battery and recharge?

If the battery charge LEd is blinking do NOT leave the battery in the unit.

It's well and truly dead.

Regards,

James

I took the battery out, but I know the previous user left it in all the time (it was dead for at least a year of regular use). what are the chances this did damage?

If it continues to operate on AC, you've dodged the bullet.

Leaving a dead battery in a Thinkpad will sometimes kill the DC/DC card.

Regards,

James

oh okay good to know. The AC still works great. BTW what is a good price for a new Li-Ion battery?

I see new ones on ebay all the time for $60 plus shipping. I bought one and it generally goes for about 2 - 2.5 hours in my 770x w/PIII 500Mhz.

guest again wrote:oh okay good to know. The AC still works great. BTW what is a good price for a new Li-Ion battery?

The following experience may or may not be useful to you, but I thought I had a "dead" battery too. But I did a couple of things that seems to have kick-started the battery operation.

I attempted the batteryless approach for a BIOS UPDate, but the machine wouldn't cooperate. The only thing that looked promising was the bootable image of the Update disk. I allowed the program to "check" the battery and it reported that it won't proceed because the battery was not fully charged. Right after that, something quite miraculous happend. I noticed that the battery seemed to be charging! It went from 0% (and flashing) to 1% (steady) then 2% in about 5 minutes. Then it climbed to 3% 10 minutes after that. Then it climbed to 4% about 10 more minutes later. I walked away from that for about 40 minutes.. but the next time I looked at the LCD dispaly, it reported 100% !!! I immediately applied the BIOS Update. I then followed the intructions and did the "Initialize" in Setup. Then on the next full re-boot, I was greeted with Window's sounds!

SO.... I am guessing that maybe the forced battery "detection" allowed it to get initialized and resetting something internally to start allowing the battery to charge. I don't understand it! As I am writing this, I testing the charge. The status changed from 100% to 90% in 20 minutes. Hopefully this will be linear as I simply leave the TP to run with the display on and the hdd spinning.

Thanks for the info. I just bought a new Li-ion battery on ebay (63$ after shipping and in a sealed ibm box). I have one question about it. I tested it out once after letting it fully charge. After putting my 770z back in the ac, the battery only charged to 97%. Do these batteries have memory and therefore need to be 'used up' in order to fully recharge or did i do something wrong?

Finally, I received an adapter to put a second battery into the cd-rom drive slot, I will try that with my old battery just to see if it works. I will update if it does. And I will try that bios suggestion as well.

guest user (again) wrote:Thanks for the info. I just bought a new Li-ion battery on ebay (63$ after shipping and in a sealed ibm box). I have one question about it. I tested it out once after letting it fully charge. After putting my 770z back in the ac, the battery only charged to 97%. Do these batteries have memory and therefore need to be 'used up' in order to fully recharge or did i do something wrong?

Someone told me that Li-ION batteries do not have the memory effect problem nor can they revitalized by de-charge/re-charge cycles. Infact, Li-ION have a limited life span, approx 300 re-charge cycles or approx 3 years.

Thanks for the info. I got the battery to charge to 100%, it had to be below 92% to charge fully for some reason. No luck with the second battery though, safe to say it's dead (it is the original battery).