Hi, I just fixed a small bluetooth speaker (fits in your hand) and I noticed it has a small battery of 3.7V 150mAh, really simple rechargeable battery with a small protection circuit and just a positive and ground.
My question is... Can I simply solder 2 batteries in parallel (stack them together) so I have 300mAh in total?
I guess the charge circuit checks if the voltage of the positive and ground reaches about 4.20V, and once there, stops charging. So it would simply take more time to charge, but it would last about double of the original design. Is there any problem I might have thought about?
Will the batteries stay all the time more or less at the same voltage?
What if not? (is it even possible)
Batteries charge really slow (compared to today's smartphones and stuff) so heat is not a problem.
I've done sometimes battery enhancements of devices, like putting a battery with more mAh, but never used 2 stacked batteries (although I've thought about that for years "what if..."). Oh, the reason why I want to stack 2 is because the area I have to install the batteries is about 25mm x 20mm. I can't fit any 300mAh battery because they measure 35mm x 30mm or something like that, and the only way to increment is to stack 25x20 batteries.
My question is... Can I simply solder 2 batteries in parallel (stack them together) so I have 300mAh in total?
I guess the charge circuit checks if the voltage of the positive and ground reaches about 4.20V, and once there, stops charging. So it would simply take more time to charge, but it would last about double of the original design. Is there any problem I might have thought about?
Will the batteries stay all the time more or less at the same voltage?
What if not? (is it even possible)
Batteries charge really slow (compared to today's smartphones and stuff) so heat is not a problem.
I've done sometimes battery enhancements of devices, like putting a battery with more mAh, but never used 2 stacked batteries (although I've thought about that for years "what if..."). Oh, the reason why I want to stack 2 is because the area I have to install the batteries is about 25mm x 20mm. I can't fit any 300mAh battery because they measure 35mm x 30mm or something like that, and the only way to increment is to stack 25x20 batteries.