I work at a large manufacturing plant and we have a dozen or so of those portable electrical defibrillator devices at our location. We change the batteries every year just to be safe. I have been given permission to take these 'spent' batteries home for reuse. They are 2.0 amp hour, 12v SLAs about the size of a largish laptop battery. Most (all?) have never been used and have been kept topped up by the (presumably smart) chargers in the defibrillator packs. I'm guessing they are still in pretty decent condition.
So my question is, would it worth connecting four of these in series for 48v and then placing them in parallel with my four 9ah SLAs in my X-500 scooter? Simple math would say this will give me about 20% more range. Or are these so small as to be not worth the effort and extra weight?
If I do use them, would it be better to have two independent circuits with a switch or just simply put the new pack in parallel with the existing one? If I do the latter, will I have any problems charging the whole mess at once with the stock 1.5ah charger? Thanks in advance for your advice.