I've got a T450s with no internal battery and a 6-year old external battery. Even if the battery will not hold a charge I'd expect it to be recognized. Any ideas? I've tried the reset procedure and installed the software below.
Lenovo Power Management Driver for Windows 10, 8.1, 8, 7 (32-bit, 64-bit) - Laptops
Lenovo Settings Power Manager for Windows 10 (Version 1703 or Later) - ThinkPad
The external battery is 6 years old.
Do it well, worse becomes itself
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If you unsure whether the battery is Lenovo genuine provide its surface with stickers/symbols to check them out.
Do it well, worse becomes itself
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Double check if contacts are clean (Maybe use some contact cleaner like WD40 a little).
It could be the controller is relying on a charge in the battery in order to accept new AC charge or being able to comminicate at all. If the battery is fully flat the controller chip inside the battery might not be able to even start up anymore, noticing the AC charge, and accepting it. But this is just a idea. Personally I would design the controller in a way that it also could run of external AC power ;)
What ya can try (Disclaimer : Just an idea, it could damage your battery) is warming the battery up in some way. Put in in the sun for half an hour, or blow it a bit with an hair dry-er so that it is about 30-45°C. It might accelerate the chemicals just enough to produce a high enough voltage for the controller to run again and be able to read it out, or even maybe accept charge again.
Remember that if it really is flat the battery migh already be seriously damaged, getting it revived again after a flat chage might highten fire/explosion risks.
I've ordered a replacement. Given the age of this one, that might be the case that it's just too "gone" to be recognizable.
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So. For some reason, in MY case, without an internal battery, the external battery is not recognized. I installed a new internal battery and now both are recognized. So I guess the external was good afterall and this model requires an internal battery at a minimum.
BUT
I also ordered a replacement external battery. Turns out it's a larger capacity version with rubber feet on it which is nice. The label is identical to the one above except for recent date markings and the mAH rating. This battery is "randomly" recognized. Sometimes it's shown and with the laptop not being touched at all will disappear from the battery status popup.
