A little while ago I tried to turn it on again, to be used in a project idea I have. However, it had given up the ghost. After opening the case and inspecting it, it turned out that the battery was completely dead. Zero volts over the cells, and the balancing board corroded beyond recognition!
Turns out, a suitable battery was expensive, more expensive than I was willing to spend on this project. I thought, therefore, I could hack an inexpensive RC pack. So I bought got hold of an RC pack and a new balancing/protection board.
After peeling everything (carefully) apart (because they can explode), I de-soldered the cells free. If you attempt this, please take appropriate safety precautions. I then soldered the cells onto the protection board, and applied copious amounts of capton tape.
To get the protection board working (activation), a charging current needs to be applied. Otherwise no voltage will appear across the load output. (This needs to be done every time the cells are disconnected from the board). The simplest solution it to connect the new battery to the tablet.
I had to reflash the tablet with firm ware, probably because of the prolonged powerloss.
And then everything worked perfectly! Battery reading and everything!! Well chuffed :) I reckon there is about an hours use on full screen brightness. Not a huge amount, but for what I'm going to use it for, it doesn't matter anyway.
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