DIY CC/CV Charger

[Jym]

Is anyone aware of a 10-40A (DIY?) CC/CV charger circuit that's pretty much "hands off" (once configured), meaning plug into wall, charges, then shuts down without any user intervention?

I can provide the DC source, it's the CC/CV and shutoff when full that I'm looking for.

Closest I've seen so far is something like this:
https://www.qskj.cc/shop/product/19...p-power-supply-module-qs-4884cccv-1200w-79174

But it's quality/reliability/safety (blowing up) is questionable from the reviews I've read.


I did find this:
https://www.microfarad.de/li-charger/

and I suppose it could be modified for the high currents I'm looking for, but seems a bit overkill.

I could use a solar charge controller and DC power supply, but $90 for 20A and $150 for 40A seem excessive,
something in the $15 to $30 range would be ideal.

Thank you!

 

[daromer]

I would say you dont get a reliable system like that for that money without cheaping out. Theres a reason why the gear cost some....


I would use a standard CC/CV ebay controller and then add the timer. I would say it will cost you around 100-200USD as starter. Thats what my units cost here that i use. I have not seen any cheaper that can handle the output properly.

Ie PSU + controller. DPS3020 or other

 

[jonyjoe505]

I have use that boost converter (1200 watt) on your link and it works pretty good as long as you don't max it out, anything made in china is rated double what it can actually do without heating up. Maybe use it at 15 amps with a powerful fan blowing on it, but they are cheap enough that you can use 2 of them at the same time. I've had fuses blown on boost converters when charging at high amps and not enough cooling air.

One thing about cc/cv converters that I have used, it takes many hours to fully charge a battery, leave it connected long enough and it turns off. But usually once it reaches the set voltage and current drops to 100ma the battery is full. I have use them to charge li-ion and lifepo4 and it gives the battery a very good safe charge.


Once voltage/amps is set the boost or buck converters are plug and play, just connect input output and it starts charging. I would add a volt/amp LED meter (less then 10 dollar) to monitor the charge status in real time.


Just make sure your input and output voltage are not close to each other. If your input is 12 volts then the output has to be at least 18 volts if you want max charge amps. If your input is 12 volts and you want to charge to 14.4 volts, you won't get max amps output.



this is a 6 amp buck converter I built, 14.6 volt output. Works extremely well. The specs say its capable of 15 amps but I would never use it at such high amps.