x220 dead slice battery.

[evening_hunger]

Got myself a new/unused 19+ slice battery off ebay (not actually new, but its condition was superb). It had 11 cycles, 100% capacity, no problems. As I'm on linux and hadn't had the chance to see its diags on Windows (yet), I looked at what my Debian had been reporting and all was cool.
Well, I do remember when first inserting it into a running system and powering it up, the system died. I ignored it, rebooted and all was ok. Used it just for few days (to see how it goes) and shelved it for two or three weeks.
As I've been using it again a bit yesterday, I thought I'd leave the system on AC for the night. AC is plugged into the slice, as you know. And so, I woke up to see the battery behaving strangely. It has control LEDs to check its status - those were all blinking, and the first one was red. Also I noticed the battery hasn't charged at all. Later on, I plugged in to three different ACs, and still no joy, once connected, flashes all leds (four green, one red) and doesn't charge. As you probably know, the 19+ battery can be charged on its own sans laptop. But it doesn't.

I got the idea that perhaps once I discharge it, something will change - as in its onboard system could reset etc. That didn't help as well, behaves pretty much the same. I'm planning on pluggin it to some Windows system (my wife's x230 once she agrees...) and seeing what it tells me.
Has anyone seen something like this? Any ideas? Is it a new and shiny brick? (well, brick with 5 working leds...)

[evening_hunger]

Edit: I got to test it in Windows. Quite peculiar: the system sees the battery, and says it in perfect condition. Says it has eleven cycles, 100% original capacity etc. In the picture, everything's okay with it. But at the same time, it says it won't charge the battery (for no reason). AC is plugged into the slice, diodes flash repeatedly on the slice, and that's it. No charging, and since I depleted it it stays at 0%.

[RealBlackStuff]

Try removing the main battery from the X220, then attach the slice, boot and see if it will charge now.
Fully depleting that battery could also have killed it!

[evening_hunger]

Well its behaviour was quite identical before depletion: it wouldn't charge.
Thanks for your advice. I did that, no joy. The battery lits up its LEDs (which this time just stay on all the time) but the power is not even passed through to the laptop and so the system won't power on. That's all.
All in all, to my suprise I even got the partial refund for it. But it's still pain to be left with a dysfunctional device, especially as I think I could have good use for extra juice in coming weeks...

[hhhd1]

what happens when you connect the battery while the power is connected to the laptop itself, and not through the battery?

[RealBlackStuff]

I have not yet had an X220 in my fingers, but the other day I had a T23 which would not charge its battery.
It being such an old machine (and having worked on many of them) I remembered that there is an inductor near the battery connector (dark grey square).
There are a few of those on the T23 mobo, and over time they come loose or disconnect partially.
Removing them, removing the corrosion, and resoldering them back usually solved the problem
Look at this picture in grid-position G6: http://www.rkawakami.net/ibm_t2x/mobo_top_72_legend.jpg
Since the X220 is already 4-5 years old, a similar problem may exist if there is such an inductor near the battery connector.

There are 2 fuses F17 and F18 in the battery charging circuit. Maybe one is gone?