There are many of the following solar-powered chargers on the market, all with the same component footprint.



Some say they are for charging lithium, others for lead acid, and some for both.

Does anyone have practical experience of using any of these?

From what I can gather, the main chips are CNxxxx type but
CN3767 Lithium Only
CN3791 Lithium Only
CN3767 Lead acid Only
CN3722 Lithium Only

Can you get away with dropping different chips into the same pcb, with all the same components. I know that what is shown might not be what you end up getting.

But I have 2 of the modules all with CN3767 IC's in them. Which are advertised for 3S lithium and should have CN3722 chips in them, when in fact they are lead acid only ??? and I wanted lithium chargers

 

They will be a bit rubbish for solar charging, as they work at a fixed solar panel voltage, whereas the MPPT point is highly temperature dependent.

 

They will be a bit rubbish for solar charging, as they work at a fixed solar panel voltage, whereas the MPPT point is highly temperature dependent.

A follow-up, from asking questions of the aliexpress sellers, shows that what IC's are shown in their photos and in the description is not what is being supplied in most cases. So you could get a lithium controller, which you think is for lead acid.

 

A follow-up, from asking questions of the aliexpress sellers, shows that what IC's are shown in their photos and in the description is not what is being supplied in most cases. So you could get a lithium controller, which you think is for lead acid.

Nice way to start a fire!

 

The same HARDWARE should be controllable to charge both types of batteries. The control programs would be quite different though. But both could be loaded into similar prom types.

BUT, just because it is possible does not mean it has been done.

 

Thanks for all the comments.

But there is a chip BQ24650 available, but at quite a high price, that can charge lithium and lead acid. However, each type of battery has to have its parameters set each time.



Just the chip alone is about £10 each to buy. So I thought I would gamble on buying a module at this reduced price.

But I have never seen a PCB with so many Via's. It seems as though it's going to get very hot.





I assume they are all for cooling ?? as if running at 10Amps, there is going to be a lot of heat.



There are 2 rows of 6 pads in the middle of the board, referenced as excon/Mcu on the supplier's official photos. But nobody seems to know what you can do with them??

Does anybody have an idea?

They are also gun-ho with slapping on heatsink compound ( very rubbery), which does not look neat and professional.

Does anybody have any experience with this, and what are excon/Mcu pads?

 

NOTE THAT THERE IS NOT any actually specific data included in that whole sales post!
ANY HONEST organization will provide a lot more data that is actually both useful and accurate.

So my advice is to abandon the screen-door sales company showing that listing and deal with an honest organization that is willing and able to describe in detail exactly what they are wanting to sell.

 

NOTE THAT THERE IS NOT any actually specific data included in that whole sales post!
ANY HONEST organization will provide a lot more data that is actually both useful and accurate.

So my advice is to abandon the screen-door sales company showing that listing and deal with an honest organization that is willing and able to describe in detail exactly what they are wanting to sell.

I take it you have no meaningful response to my legitimate post.

"Does anybody have any experience with this, and what are excon/Mcu pads? "

 

GIVEN that we have no data about the part values and no circuit to see, and no hint about what the control scheme is, it will require an individual with vastly greater capabilities to describe what needs to be done to assure that it will correctly charge lithium batteries.
Certainly your post and your request are legitimate. And the ad attached may have been correct, but totally lacking in needed information.
I no way am I faulting you, the Thread Starter. it is the seller who is the problem.

Possibly one could visit the website you mentioned and deduce the correct actions. Correctly selecting the software options for an unknown MCU controlling an unknown circuit to charge a specific battery type is beyond my abilities. So any advice in that area on my part would be a pure guess. Based on that, I submit that the advice I gave was entirely correct, although certainly not what you were hoping for.

 

Can you get away with dropping different chips into the same pcb, with all the same components. I know that what is shown might not be what you end up getting.

No.
Look at the data sheets for typical use schematics, and theres a good chance that is what you’ll find. Board quality looks poor, but that’s a trade off with price.