Sony ERA-110B Recell

[TonyBe]

Hi folks,

i once again run into a problem which i cannot solve by my self after hours of research and fiddeling with the hardware.

I'm currently having a Sony Aibo RoboDog on my bench which works perfectly, except the dead batteries. This batteries are "Sony ERA-110B".

After ordering fresh LiIon cells for the battery and fitting them into the plastic enclosure, i'm getting no voltage at the output. When trying to charge the battery, the station just shows "End of Life detected". Since the cells are definetly charged, there must be some FET Transistors on the electronic which kills the output voltage when the battery is stated "empty" (even though the cells are charged).

After searching on google, i quickly found this guy, which does a great job on recelling the packs but sadly stoped his service last year. He have designed a reader tool for the batteries and provides the src to that:
https://aibodoctor.com/2017/11/10/aibo-battery-refill-tool-for-era-110b/

Even though it's a very great job that has been done there, there is not much information about the functionality in detail. He says that the pcb needs to be replaced once the battery is empty,.. but i really want to find out, why (and if it's possible to "reset" the hardware in any way).

If I understand this correctly, there is a COM between the battery and the charger which gives a lot of information about the cell. To do this, a one-wire HDQ interface is used. Since non of the components on the batterys PCBs is labeled, i have no idea, which chip is doing that job there. I'm starting to think, that the controller on the pcb does have some kind of write protection on the registers, which forces a new PCB to be designed and takes care of charging controll a.s.o.

Now my "question" (kind of):
does anyone of you have any kind of information about the battery electronics? There is one big IC on the pcb (36-QFN) which says "SHARP LU5K811" on it,... can't find anything about that.. Does anyone of you may have some ideas what to do next?

Really looking forward to your sugestions

Thank you all in advance!

Kind regards!
Tony

[amyk]

If you look at the battery management ICs which do have datasheets (e.g. TI BQxxx series) you'll find that they do have self-destruct functionality and tamper detection as well as "password" protection (although for the laptop batteries that these are widely found in, someone may have bruteforced it.) It sounds like yours has a permanent protection, hence the need to replace the board with a new one. There is also a fuse that gets blown. Do research into laptop battery recelling for more information.