I found some more information.
(I posted orig>
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The battery, which is not the original, but a replacement bought from
> China, is bulging, and made the case to open.
>
> There was no exact replacement. I had to desolder a chip from the
> original battery and solder it to the replacement. Not shown well in the
> photo, it is at the other end. I added a close up photo of the chip. >
> The original battery was LP404252ARU, with three wires. One
> for some sort of sensor. Device does not power up with two wire
> batteries. On Aliexpres on 2020 I found a "404252 3,7 V 1200mAh
> batería recargable de polímero de litio para Kobo Touch E-book
> MP3 MP4 Lampe altavoz juguetes banco de energía móvil 404050".
> The links from back then are dead now.
>
> I have not searched yet.
>
>
> I bought another reader a year ago, in May. A Kobo Libra Colour. This
> one the company said they would process repairs. Perhaps means spares
> will be provided.
>
>
> Perhaps I should do something to power up the old reader and do a
> factory reset, or something, in order to remove the DRM thing from it
> (you can only have six on Adobe Digital Editions)
>
>
> (I don't see a group on epub or ebook readers)
On
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they sell the original battery for £28.98 inc. VAT.Wow.
Amazon has the two wire version (I would have to replace the PCB)
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. There is no price on the page, but google says "US$34.78".Aliexpres has the one I bought and that bulged some years later:
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for 4,49€.These are the instructions I followed the last time:
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It is 3.7 volts, so I will probably rig three standard rechargeable batteries, size AA or AAA, in a battery holder, and connect it temporarily, so that I can remove the registration.