'recondition' an old battery

[thefragger]

so I bought my thinkpad on ebay and the battery is in pretty poor condition-- I only found this out after I loaded the IBM software that allowed me to view battery stats.

remaining percentage: 95%
remaining time 1:25
full charge capacity: 16.60Wh
design capacity: 47.52 Wh
cycle count: 514

manufactured date is the same as the first-use date, which I find odd (2004-09-09). now, I was searching google about battery reconditioning and the like, and google produced an interesting result dealing with thinkpads.

http://www.levien.com/tp600-battery.html

(First sorry for my english )

I have making some experiments with my thinkpad.(I have the same problem of the jumping bat), and I have reach the conclusion that the "intelligent" battery is really stupid. The problem is software, but it is not in the firmware or something in the thinkpad, but it is in the program of the microcontroler in the battery.

The solution for the problem is easy: Recycle the battery, but...not as IBM says. The microcontroler does not let you discharge all the energy from the bat, so I dont let the microcontroler of the bat comunicate to the thinkpad, and by this way I can discharge all the bat, and then get full charge.

The way to eliminate comunication is very easy: there are 4 pins in the battery, the 2 in the middle are the microcontroler comunication to the thinkpad, so before put the bat in its hole, I put 2 little papers over that pins, and I get power on. Now you dont know when the bat is empty, and the computer will power down in any moment, but you can discharge completely the bat.

You need to do this some times to recover the capacity lost.(at least some of it) A warning: when you charge it, dont use the papers, or you could overcharge the bat, and it is the worse thing you can do to a battery. If you dont understand the process (I know my englis is very poor) I could send you a couple of pics.

now, that sounds a little crazy to me, but can anyone see any truth in this? can't LIons suffer from undervoltage?

if this is true, I sounds like it's worth a shot.

comments?

[christopher_wolf]

This is a T40p, right? Those instructions were for a 600 and one can't be sure if a similar enough pinout was used on the T4X Batteries. From the stats you gave of the battery, it doesn't look as if it is going to come back to any significant extent as it is already at around ~16.60Wh from a design capacity of 47.52Wh. Even the little bit of charge you can squeeze out of it isn't going to help all that much.

Why not just get a fresh, new T4X Series battery?

[pksw]

Does reconditioning actually work? I have a t41p, and my battery is the 9 cell version. Instead of holding approx 75 amp/hours, it only has about 18 amp/hours at full charge. It is about 2 years old.

I've tried draining it to 0%, and doing a full charge, but it won't get to near the maximum capacity. I get less than 30 mins power on battery now.

I took the risk and bought a "genuine IBM" 9 cell Li-Ion battery on ebay today for approx $US 75, and hopefully it will solve my problems.

I'm doing a full charge of that battery at the moment, then will let it run through a few total discharge/recharge cycles. I'm not sure whether this actually does anything on Li-Ion batteries - everyone has a different opinion.

To the original poster - I'd be careful fooling around with wires and the battery - sounds a bit dangerous to me! It sounds like your battery is as dead as mine.

[AIX]

A few years ago I tried to recondition a TP 600X old battery following the steps above; nothing positive happened, the batterry capacity remains the same. So - it won't worked for me.

sorry for my english

[Talon88]

:::

The batt is at it's end of life....

:::

full charge capacity: 16.60Wh
design capacity: 47.52 Wh
cycle count: 514

[Lazarus]

You need a specific repeating cycle of discharge and slight(!) overcharge to re-condition a battery and simple paper slip trick won't do the trick here.

You are basically trying to reverse chemical degeneration that has occured in the battery and the electronics you got in your laptop are just not designed for that.

Also, you need to be cautios not to damage the controller chip in the process or you can overload your battery to the point of a firy explosion.

And I ain't kidding here. You can get realy hurt badly by that stuff (--> Sony).

[mikek]

Pretty sure you're on borrowed time at >300 cycles. 514 cycles means the battery is knackered. Save you self some pain - buy a new one!