Winners DC-DC converter/charger module

[Deere John]

Hi! Anyone tried this little gadget?

https://www.ebay.com/itm/10A-DC-DC-Adjustable-CC-CV-Step-Up-Power-Supply-Module-LCD-Display-with-Case/323083859271

Seems fantastic. I actually bought three of them have just tried it a little, it is balancing up my pack now to 70% charge for storage. Has it set to 2.0 Amp (@ 37.4V) as my standard charger. It pulls 5.77 Amp from my 13.5 V PSU (almost 80W then).



I will give this one a test period, later I might build a complete box with PSU and charger in one piece.

It feels great, just hope the module is reliable and don't mess something up.

 

[spanos]

Hi! Anyone tried this little gadget?

https://www.ebay.com/itm/10A-DC-DC-Adjustable-CC-CV-Step-Up-Power-Supply-Module-LCD-Display-with-Case/323083859271

Seems fantastic. I actually bought three of them have just tried it a little, it is balancing up my pack now to 70% charge for storage. Has it set to 2.0 Amp (@ 37.4V) as my standard charger. It pulls 5.77 Amp from my 13.5 V PSU (almost 80W then).

View attachment 23763

I will give this one a test period, later I might build a complete box with PSU and charger in one piece.

It feels great, just hope the module is reliable and don't mess something up.

Forgive me if I am missing something !......but on a normal charge (so to 42v) isn't this lacking in safety?

A standard lithium charger is mildly clever in that it senses voltage and taper charges from a certain point

Isn't this a blunt instrument by comparison ? It will charge at 2a all the way to 42v and then rely on the battery bms to go into balance and bleed mode ?

I'm sure I'mmissing something here...

 

[danielrlee]

Forgive me if I am missing something !......but on a normal charge (so to 42v) isn't this lacking in safety?

A standard lithium charger is mildly clever in that it senses voltage and taper charges from a certain point

Isn't this a blunt instrument by comparison ? It will charge at 2a all the way to 42v and then rely on the battery bms to go into balance and bleed mode ?

I'm sure I'mmissing something here...

This DC-DC converter gives a CC/CV charge profile, just the same as a dedicated Li charger does.

 

[Deere John]

...yes, it works the same way. Actually it seems to have more features than it looks like. It ramps down the charge current when closing in on set voltage level. And you can always monitor voltage/current level, very neat. Yesterday I tried with a laptop PSU 19V / 4.2A. It should be just enough for charging with 2A I thought. But since my second unit was not set to 2A but more it just blinked with the charge light, indicating that it couldn't charge because of the weak PSU.

 

[spanos]

Thanks both

It does look a very cool bit of kit then

 

[Deere John]

Yesterday I tried with a laptop PSU 19V / 4.2A. It should be just enough for charging with 2A I thought. But since my second unit was not set to 2A but more it just blinked with the charge light, indicating that it couldn't charge because of the weak PSU.

...oh boy! I have bad news. This feature with the blinking light. This is NOT a feature, it behaves like that because it doesn't ramp down, it malfunctions. And it brakes! Actually that made my second unit brake down. Unstable output current now and it makes a whining sound.

I thought it was because of PSU-failure. But yesterday I brought home just THAT PSU and tried on my main unit at home. Same phenomenon. And... same failure. Now I have two units that doesn't work!

I'm very sad. I really liked them! It worked very well using a good enough PSU which I had at home.

Well well. Such is life.

I did some deep googling and found interesting options though.

Ruideng control:
https://www.aliexpress.com/store/product/RD-DPH5005-Buck-boost-converter-Constant-Voltage-current-Programmable-digital-control-Power-Supply-color-LCD-voltmeter/923042_32840324731.html?spm=2114.12010606.layer-91o8cf.258.6b595bc5tnnuYK&scm=1007.14677.92111.0&scm-url=1007.14677.92111.0&pvid=2ae5d49b-0368-460f-850f-f2d3c1427212

But I did not fall for that option, it requires some extras to get a complete charge station.

Long time ago I read about this MeanWell HLG-series LED driver:
https://www.meanwell-web.com/en-gb/ac-dc-single-output-led-driver-mix-mode-cv-cc-hlg--185h--42a

I actually bought a such instead, because I thought that should be a more solid solution and also found a good price (for just that 185W model).

But it is lacking monitoring display, so I bought one of these:
https://www.ebay.co.uk/itm/181573053894

I have a feeling this will get very good. Only concern is the CC/CV characteristics curve, it looks very square in the data sheet, I hope it will work more like normal charge curves.