PCeBiker
No-Hands No-Pedaling No-Credentials
- Region
- Canada
This is a "standard" 12 volt Li-Ion battery pack,..
3 cells in series. No BMS.
(I peeled off the plastic shrink wrap)
It was from my mother's electric bathtub chair/lift.
It was charged with a simple 12vdc power adapter that was always plugged in and connected directly to the battery, so it was always charging.
(the adapter didn't have enough power to operate the chair on its own)
There was never any "overcharging" type issue because the cells never reached full charge, but mom did manage to kill the battery.
(she thought that if she held the "UP" button on her remote long enough, the chair would eventually lift up higher. Lol
Took 5-10 minutes to kill the battery pack.)
Even when the battery pack died, it didn't burst into flames. It just lost most of it's capacity, and would only lift the chair an inch then you'd have to wait for it to "recharge" to get another inch of movement.
(We ended replacing the battery, and adding a switch to the lift mechanism that would turn off the power when the chair was at the top position.)
FYI, you can't connect a simple 3 cell lithium pack to a car because the alternator running voltage is frequently over 14 Volts.
(12V car batteries charge at ~13.8 Volts)
That would be 4.67 Volts per cell, and you'd cook the cells.
If you added a fourth cell in series, each cell would only be at ~3.5 Volts which is almost useless and too close to "empty".
3 cells in series. No BMS.
(I peeled off the plastic shrink wrap)
It was from my mother's electric bathtub chair/lift.
It was charged with a simple 12vdc power adapter that was always plugged in and connected directly to the battery, so it was always charging.
(the adapter didn't have enough power to operate the chair on its own)
There was never any "overcharging" type issue because the cells never reached full charge, but mom did manage to kill the battery.
(she thought that if she held the "UP" button on her remote long enough, the chair would eventually lift up higher. Lol
Took 5-10 minutes to kill the battery pack.)
Even when the battery pack died, it didn't burst into flames. It just lost most of it's capacity, and would only lift the chair an inch then you'd have to wait for it to "recharge" to get another inch of movement.
(We ended replacing the battery, and adding a switch to the lift mechanism that would turn off the power when the chair was at the top position.)
FYI, you can't connect a simple 3 cell lithium pack to a car because the alternator running voltage is frequently over 14 Volts.
(12V car batteries charge at ~13.8 Volts)
That would be 4.67 Volts per cell, and you'd cook the cells.
If you added a fourth cell in series, each cell would only be at ~3.5 Volts which is almost useless and too close to "empty".
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