I have two identical 2A 42V li-ion chargers. Is it safe to connect them in parallel to charge my 10S4P pack, potentially doubling the charge speed?
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Probably, sounds scetchy tho. And it wont be twice as fast.
I don’t think it will work. Your two chargers probably output similar but slightly different voltages. That slight difference will cause the current to flow from the higher voltage charger to the lower one. The chargers are generally not made with protection to stop this and you will probably smoke the lower voltage charger.
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No, you’d want to use a 4A Charger.
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One will trigger the voltage cutoff of the second one…
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Some will work, some won’t, I’ve done this plenty of times with all kinds of chargers and not once have I have an issue
The only time someone had an issue was when they used an EWheels 100v charger with something else
But most of the times identical chargers can be plugged in parallel to double your amperage, but who knows, you can take your chances
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U’re right. One charger will recieve backwards current due to voltage differences. NOT SAFE.
Chargers already receive backwards voltage from the battery, so that’s not an issue.
It highly depends on your specific charger and how its specific circuit is built. Likely there will be no documentation on that. I would recommend a DC ammeter (multimeters usually have this function) and test it out on a concrete surface away from flammables, but only if it’s REALLY important to you.
In general, I can’t imagine the scenario where buying a $50 4A charger is a less attractive option. That’s $50 well-spent. Unless you like risking structure fires.
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For safety make an adapter with a pair of diodes, this way the current from one can’t flow into another
The battery will charge to a slightly lower voltage, but if you really need 100% just unplug the adapter and plug just one charger
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Thanks for all the replies and suggestions. I’ve decided it’s not worth the risk and will instead go for a standalone 4A charger.
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Out of interest, did you use any special components/circuitry or literally just wire the chargers in parallel?
No special circuitry, just connected them in parallel and all is good