Lipo charging times AC vs DC

Hey guys,

After some help as the maths of this always confuses me.

I’ve got a HOTA D6+ Dual Channel 325W 15A AC/DC Battery Charger – NewBeeDrone on its way to me and went with this as it’s reasonably priced and will charge one lipo at 210w or two at 150w each.

Firstly how do I figure out how this compares to the recommended 1C charging rate for my 6S 10AH packs? Will I even get close?

Note I will always charge 2 packs at once

Secondly if I get this isdt power supply, it’s rated for 600w output 24vdc 25A iSDT SP2425 600W Smart Power Supply - Hobby Station

How much closer does this get me to my nominal 1C rating? If I’m still within can I assume I am halving the charge time from AC (going from 150w per battery to 300w)?

If this is over powering for my pack would the cheaper 400w pack be better suited (an extra 50w per battery)

The first charger will charge two batteries at 7.5A each(0.75C), the second charger will charge at 1.5C each packs but wont balance them

I think you would make your life easier if you find a 10-12s skateboard battery and a laptop sized charger for it

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If your charger can do 150W at 6s than that is a charge current of 6.75A. 150W/(6x3.7V)

1C of your 10Ah pack is 10A charge current.

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Thanks man, but the second link isn’t a charger, it’s just a DC power pack for the charger to provide higher power than the standard AC plug

Ah ok, so if I got a 400w DC supply and charged at 200w per 6s I would be close to that 10A 1C value?

please check cell temperature when charging 5a+, the way people used to do it was meanwell adjustable psu+ bg-8s cell monitor/balancer. Hobby RC chargers are kinda annoying since you cant charge the whole batt at once you have to take it apart in your case

I’m not needing to take anything apart in my case. I have 2 x 6S lipo batteries and this is a dual charger so can charge both at the same time, they are connected with a series adaptor so just plug and unplug.

Good point about the temperature. This balance charger has built in temperature monitor through the discharge plug but will definitely keep an eye on it when first using with a DC power supply.

I’ve made the decision to get something like this - Geekcreit® ac 110-240v input to dc 24v 17a 400w switching power supply driver board Sale - Banggood.com

It’s a cheaper option, i have all the necessary cables and it will get me closer to 1C. Will do some testing with a multimeter first too to make sure i haven’t bought something that will burn my house down

If you run that charger on AC your total input power is 300w, and while it says each channel is 210w, that just means running one channel you can only get 210w instead of 300w, but if you run two channels it’s limited to 150w ea.

Charge amps = watts / (4.2v/6s)

150w (dual) = 6A or 0.6C
210w (single) = 8.3A or 0.8C

If you run that charger powered by that 600W DC power supply and charge both batteries at the same time:

300w ea = 12a or 1.2C each.

EDIT just saw the Geekcreit/meanwell power supply. That will work fine, just won’t balance. the HLG series is a better plug and play option IMO

320w
480w
600w

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I’m pretty sure that they’re not planning to use the power supply alone to charge the batteries, but rather to power the dedicated lipo charger. The charger’s onboard power supply is the limiting factor, so using an external DC source allows higher power.

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packs are measured in amp·hours (Ah), not amp·henries (AH)

C means h-1, or “per hour” in a similar way that Hz (hertz) means “per second” or s-1

So 1C at 10Ah is 1C · 10Ah = 1h-1 · 10Ah = 10A

But this is only an upper ceiling. Charging at lower rates can slightly extend pack life. Though proper balancing and cutoffs seems more important to extend pack lifetime.

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Yes, that’s right, still using the balance charger, just spending a few more dollars to jump from that 150w per battery to 200w per battery, it makes a morning ride and an afternoon ride a real option :smiley:

I can’t help but imagine Peter Griffin telling me about Amp Henries when I read your post.

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you would have gotten more mileage getting a psu from amazon and a bms from lithiumbatterypcb.com