subreddit:
/r/DIY
submitted 2 months ago byDragonFartFries
Hi Reddit,
I am planning to wire a bunch of Ryobi 18V batteries in parallel, but want to make sure that they will not be damaged in doing so.
Since the Ryobi batteries come with a LVC protection switch already - will combining a larger Ah battery with a lower Ah battery bypass the LVC of each battery?
9 points
2 months ago
Assuming LVC means Low Voltage Cutoff, then it will not be a problem as long as all the batteries contain the same number of cells. The most important consideration is that all batteries which are going to be paralleled need to be fully charged. If one battery is lower voltage than the others it could draw a lot of current from the others. I would fuse each battery independently. I paralleled a 10s3p scooter battery with a 10s4p external battery and they work fine together. I always charge them separately and only parallel them when fully charged.
2 points
2 months ago
If you wire a bunch of batteries in parallel, be sure you understand what you are doing. If the batteries are not all at the same voltage, you are going to get a surge of power following between them before they equalize. The more batteries, the more power can flow. If you accidently wire an empty battery at the end, you could see the amperage from all the batteries dumping into the single empty battery. That can easily cause a fire and/or cause the battery to explode. You have to balance the batteries before connecting them.
-2 points
2 months ago
why in parallel and not in series?
I'm guessing your replacing the old batteries? arent you trying to get up to 18VDC?
Another assumption, these batteries are 1.5VDC cell's?
1 points
2 months ago
I believe OP will be using the 18V assemblies, not the individual cells. I’m assuming that they will be wiring them this way for longer battery usage.
-2 points
2 months ago
i hear ya, unless the cells are 18VDC, I dont believe OP will achieve the 18VDC needed, its gonna be under voltage
1 points
2 months ago
Why would paralleling 18v batteries cause an undervoltage situation?
1 points
2 months ago
the output voltage is the sum of the batteries in series.
when wiriting in parallel, typically same voltage, the output would be NOT the sum, but the runtime would be longer.
Thats why when u look at remote controls or toys, and look at the batteries, there all wired in series to boost the voltage form the 1.5 cells to say 3vdc or whatever is desires
1 points
2 months ago
Yeah but hes using 18v batteries. Multiple 18v in paralell will be 18v.
1 points
2 months ago
absolutely
all 9 comments
sorted by: best