Actually, if you think of the whole backplate as a part of the battery, isn't this battery quite easy to change? You could simply sell batteries already glued

Actually, if you think of the whole backplate as a part of the battery, isn't this battery quite easy to change? You could simply sell batteries already glued to the cover, the rest is just screws and connectors. Might be a bit more expensive, but it shouldn't be too hard to do the replacement then.