PRS-950 (and others): Battery replacement ever done by yourself? Result?

[mrkapqa]

FraPe i am willing to pay you if you could send me a battery that works with the Chip.
Ordered a replacement battery but that one after an initial short life (it would give signs of life with the power cable attached) would no longer charge or hold a charge for no apparent reason.
I thought that maybe i made an error when replacing the battery, but luckily the seller was quick in offering a refund.
The EbookReader is quite damaged externally due to my unprofessional opening (thanks to the video posted here i might have learned how to do it).

I am living in Europe/Italy/SouthTyrol and would be happy to continue using the device as i find it very good one.

[Ricky D'Angelo]

Shopgoodwill has a Sony PRS-950 available for auction ending today 9/7/2019 6:39:00 PM Pacific Time. Last night I saw it and told myself I wasn't going to bid for it however this morning the inevitable happened. Hopefully, someone will outbid me since I really don't need another ereader.

https://www.shopgoodwill.com/Item/75151084

[FraPe]

Originally Posted by mrkapqa

FraPe i am willing to pay you if you could send me a battery that works with the Chip.
Ordered a replacement battery but that one after an initial short life (it would give signs of life with the power cable attached) would no longer charge or hold a charge for no apparent reason.
I thought that maybe i made an error when replacing the battery, but luckily the seller was quick in offering a refund.
The EbookReader is quite damaged externally due to my unprofessional opening (thanks to the video posted here i might have learned how to do it).

I am living in Europe/Italy/SouthTyrol and would be happy to continue using the device as i find it very good one.

Hello, sorry, I am not able to provide you a battery that works. If it does not work you have to do what I did and described. Some readers are okay without but some readers are not. In the latter case I don't think you will be able to find a battery working.

Kind regards,
Franz Peter.

[DocMeade]

Super bummed to think about letting my Sony PRS-950 die just because I can't get a battery to work! I've tried multiple after market batteries labeled appropriate for my model, but no luck, not even with the Newpower99.com version. I even soldered in a resistor to the temp sensor wire as suggested, but only managed to render the thing unreturnable! The only thing I didn't try was to make a franken-battery with the old electonics because I had already thrown the damn thing away! Aargh! I may try to get my hands on a used OEM and try that hack. If I don't post again, assume I died in a fiery blaze clutching my beloved Sony.

[Brian M]

Thought I'd do an update, we're a month shy of 2 years since I combined the OEM charge electrics with the replacement battery. No explosions, fire, swelling or other negative issues. Actually, it works as new without any oddness.

I know, it may sound daunting, but any cellphone or other electronics repair can do it without problem.

[IndyB]

Afer finding an older thread about Sony PRS battery replacement problems and solutions here, I followed the clues and instructions. Hopefully this updated guide will help others who love their PRS-950 as much as I do, to get a few more years of life out of it.

I followed the "Sony PRS-950 back cover removal" video on Youtube. The battery was a Sino Cameron battery from Aliexpress.
https://www.aliexpress.com/item/1005008536569305.html

I took a couple of photos of the inside of my PRS-950SC . Especially the battery power cable. If the PRS-950 is in landscape mode, and the circuit board has the battery furthest away from you, the red wires are on the right when looking down from above the board. That is, red is closest to the battery.

After that I gently levered the battery cable DIRECTLY UPWARD from the board using a plastic lifting tool inserted under the power cable wires.

After I replaced the battery, the ereader worked but would not charge the battery. I found a reference to this problem in Hackaday where James Hobson fixed a similar problem with a Sony PRS-T1 battery replacment.
https://hackaday.com/2016/12/04/repl...eader-battery/

The reason is that the thermistor on the replacement battery does not match the original Sony battery. Which for my PRS-950 original battery was 100K Ohm, the replacement Sino Cameron battery was 10K Ohm. So, not 100% drop-in complatible despite the claim.

But fixable!

You can check your original Sony battery's thermistor value once it is unplugged. Just put a multimeter between the white and the black lead on the battery cable. Use the small holes in the top of the power connector. Do the same on your replacement battery.

While James fixed his with a normal resistor, I found a small glass thermistor the size of a match head was available locally for less than $5. I used a couple of pieces of heatshrink tubing to insulate the leads from each other and soldered the thermistor into the white temperature sense lead.

Plugged the battery in with the back of the reader still open. Success, the red "charging" LED on the the circuit board lit up!

Reassembled it, and now my 25 year old ereader is back in action again!

WARNING- playing around with a charged or partially charged "live" Li-ion battery is only for people experienced with electronics. The Li-ion battery I got from Aliexpress had half a charge in it so it was still very dangerous for the inexperienced. I had a tin box next to me as I was working on this, in case of any issues. So I could throw any overheating battery into there and seal it.

If you are not experienced with repairing modern electronics with tiny surface mount components, find a phone or computer repair person who is, and pay them to do this. Or find a friend who is experienced and don't pay them. Well, buy them a beverage of choice or lunch once your "precious" is working again!

[IndyB]

Doh! Forgot to add in the actual thermistor value!

I used a 100K thermistor in series with the 10K one located somewhere inside the new battery. The total is 110K which is slightly out from the original spec but will read "low temp" to anything checking i.e. at 25C it will read less than 25C.

But if it gets hot it should still trigger at (say) 75C battery temp rather than 80C. Or something like that, I haven't done the calculations...

[Poremskyi]

Originally Posted by IndyB

Afer finding an older thread about Sony PRS battery replacement problems and solutions here, I followed the clues and instructions. Hopefully this updated guide will help others who love their PRS-950 as much as I do, to get a few more years of life out of it.

I followed the "Sony PRS-950 back cover removal" video on Youtube. The battery was a Sino Cameron battery from Aliexpress.
https://www.aliexpress.com/item/1005008536569305.html

I took a couple of photos of the inside of my PRS-950SC . Especially the battery power cable. If the PRS-950 is in landscape mode, and the circuit board has the battery furthest away from you, the red wires are on the right when looking down from above the board. That is, red is closest to the battery.

After that I gently levered the battery cable DIRECTLY UPWARD from the board using a plastic lifting tool inserted under the power cable wires.

After I replaced the battery, the ereader worked but would not charge the battery. I found a reference to this problem in Hackaday where James Hobson fixed a similar problem with a Sony PRS-T1 battery replacment.
https://hackaday.com/2016/12/04/repl...eader-battery/

The reason is that the thermistor on the replacement battery does not match the original Sony battery. Which for my PRS-950 original battery was 100K Ohm, the replacement Sino Cameron battery was 10K Ohm. So, not 100% drop-in complatible despite the claim.

But fixable!

You can check your original Sony battery's thermistor value once it is unplugged. Just put a multimeter between the white and the black lead on the battery cable. Use the small holes in the top of the power connector. Do the same on your replacement battery.

While James fixed his with a normal resistor, I found a small glass thermistor the size of a match head was available locally for less than $5. I used a couple of pieces of heatshrink tubing to insulate the leads from each other and soldered the thermistor into the white temperature sense lead.

Plugged the battery in with the back of the reader still open. Success, the red "charging" LED on the the circuit board lit up!

Reassembled it, and now my 25 year old ereader is back in action again!

WARNING- playing around with a charged or partially charged "live" Li-ion battery is only for people experienced with electronics. The Li-ion battery I got from Aliexpress had half a charge in it so it was still very dangerous for the inexperienced. I had a tin box next to me as I was working on this, in case of any issues. So I could throw any overheating battery into there and seal it.

If you are not experienced with repairing modern electronics with tiny surface mount components, find a phone or computer repair person who is, and pay them to do this. Or find a friend who is experienced and don't pay them. Well, buy them a beverage of choice or lunch once your "precious" is working again!

Many thanks for this very useful and detailed tutorial! I've been struggling with this problem for well over a year. Some time ago I went to the repair shop with my Sony PRS-950 and a new Cameron Sino battery, explained what had to be done, and they did it. However, once I started using it, I noticed the battery was behaving erratically and sometimes discharged in a day and a half. As of now, it's gotten even worse: it discharges one bar (out of four) per day, and I'm thinking of buying another Cameron Sino battery in the hope that it might be better quality than the current one. Please let me know if you think this makes sense.