I'm using wheelchair motors on a frame, carrying rocks, gravel and trash sort of like an electronic pony in the back yard. The lead acid batteries appear to be bogging down and do not discharge enough current. I can use brand new ones with higher discharge which solve the problem, but I am on a budget and trying to use what I have to get the job done.
Can I wire high discharge lipo batteries in parallel, in front of lead acid batteries with low discharge ? The lipo cells put out enough current, but do not have the amp-hours as the lead acid batteries do. I figured the current would charge through the parallel wiring, as long as I did not over-charge lead acid past 12.6 volts, to damage the 12.6-volt high limit on a 3-cell lipo pack.
My guess is that your lead-acid batteries have come to the end of their lives so give them a nice environmentally friendly funeral.
Lead acid batteries can normally produce a huge current - enough to destroy the battery.
I suspect if you parallel some good batteries with the poor ones you will find that all the load is taken by the good batteries.
And I have no idea whether attaching LiPo cells in parallel with Lead-Acid cells would cause the LiPos to explode. I would certainly not stand close to the experiment.
...R
PS ... it is important not to leave lead-acid batteries in a discharged state. They should get a long charge at least once per week.
You should never directly parallel or series connect batteries or cells which aren't the same type.
Its hard enough to maintain balance when they are identical...
I think what you need is a way to recharge the LiPo from the SLA battery, using the LiPo to
power the unit. Might be a fairly specialist charging circuit that can do that.
One thing you can do is combine batteries via high current schottky diodes so that when the voltage
of the SLA sags the LiPo can start coming to help. You will lose a little voltage in the diodes, and
they will need heatsinking.
Thank you MarkT, that was the advice I was looking for. Maybe I can figure out a gizmo manage power and trigger relay's to kick over back and fourth. I might need to add a large capacitor bank to draw immediate temporary power, so that the heavy robot can climb over roots without needing to take a nap.