I replaced the battery pack of my robotic lawn mower by a generic one bought on Amazon (quite expensive, but not as expensive as the original brand one that's sold at 110€!). The battery pack consists of 4 18650 cells, with a charging circuit.
The problem is that when inserted, the mover didn't recognized the battery pack and complained about too hight charging current. Unfortunately it was too late to send the battery pack back to the seller :(
So now I've
- the original battery pack with working electronic circuit, but "dead" batteri(es)
- the new battery pack with unsuitable electronic circuit, but good condition cells (at least, I think I can assume that)
The batteries specs are:
Original cells: Sony US18650V3B
- 2100 mAh / 2250 mAh
- Cut-off voltage: 2.5 V
- charge up: 4.2 V ± 0.05 V
- max charge current: 2.15 A
Other cells (from the new battery pack): Panasonic ncr18650b
- 3350 mAh
- Cut-off voltage: 2.5 V
- charge up: 4.2 V ± 0.05 V
- charge current: 1.625 A
Question 1
Can I safely replace the cells in the original battery pack (US18650V3B) by the other cells (NCR18650B)? In other words, I don't know what are the essential criteria in the specs to take into account. The replacement cells have a bigger capacity, but I don't care if they won't be fully charged by the electronic circuit.
I'm aware that I'll have to
- take care of thermal sensors, and thermal paste around them
- use a spot welder if I disassociates the cells for any reason
Question 2
I searched for new Sony US18650V3B for sale but I didn't found anything. Is there any 18650 cells that I could buy that could have the "same" specs and could be safety used? (using spot welder for cells)? Or all of that is really a bad idea, and I should go for the 110€ original brand battery? (I don't really like the idea, you would have guessed)
The only related topic I found is this one and sounds pretty encouraging. But I don't want to mess up with lithium batteries!
Thanks a lot
