Posted by: @sinclair

Can a locked battery power the laptop but not charge?

 There are about 5 types of locks which behaves differently. Most known and most frequently referred is Permanent Failure Lock which leads to full battery isolation from external world. It means neither charge nor discharge of battery is allowed. So if you mean this type of Lock then answer to your question is No. 

Another kind of Lock is Safety also known as Protection Lock. It could be caused by different safety events which is not yet very critical. Safety Lock has a feature to self-release as soon as the reason is cleared. For example light cells over temperature in charge. As soon as battery is cooled down, lock is released and battery could continue to be charged. This type of lock could lock the battery in one direction only. For example in case of overcurrent in Charge only charge activity is locked while discharge is allowed so laptop could be powered from battery and visa versa. So the answer in this case to your question is Yes. 

Same issue could be caused by using fake aftermarket battery. It could produce output power but laptop does not recognise it like genuine battery so does not charge it. Some laptops report "not OEM battery" notification in BIOS or something like this to draw users attention. 

Also same issue could be caused by hardware fault on the battery PCB in the MOSFET circuitry. We have many topics on the forum reported by our customers most of them successfully resolved. 

So we recommend to do diagnostics first. It could be done in specialized workshop by qualified technician. 

Posted by: @sinclair

Can a new, functional battery become locked due to issues with the motherboard?

 Yes. In case of short-circuit on the motherboard battery could be permanently or temporary locked. It depends on monitoring chip configuration. In this case it could not power the laptop any longer but still could be charged in case of Safety Lock. But its not your case. 

 Keep in mind that most of "new batteries" available on the market nowadays are not-original product supplied from chinese manufacturers. Many of them could not be charged in laptops due to Digital Rights Managements implemented on bios level. 

@djibattworkshop

Thank you so much for your detailed responses. It seems that narrowing down the "suspects" through logic alone won’t work – there are just too many possibilities. Unfortunately, the specialists available to me don’t seem to have even heard of concepts like "locking" or battery diagnostics in general. It always comes down to, "Let’s replace the battery – it’s not working – you must have an issue with the motherboard, there’s nothing we can do."

Thank you again for your clarifications.

 You need to read battery parameters and chip registers as a first step of diagnostic process. It could clarify situation a lot and narrow down search way.