diy solar

diy solar

One Large solar panel with 2 x Controllers

Robmc

New Member
Joined
Dec 23, 2019
Messages
20
Hi
Is it possible to run one larger sized solar panel with two solar controllers connected to two separate batteries. I have also seen solar controllers that can charge two batteries. What do you think would be the best solution.
Thanks
Rob
 
Is it possible to run one larger sized solar panel with two solar controllers connected to two separate batteries. I have also seen solar controllers that can charge two batteries. What do you think would be the best solution
An interesting question, but why do you need to do this?
What size batteries and chemistry?
Why 2 separate batteries?
Solar panels are cheap these days, SCC and batteries not so cheap.
 
Hi MBR
I am building a charging station. So the solar panel(s) will be mounted on top of a pole. Less weight with one panel up there, rather than two and a simpler install. I will be charging two lithium ion 24V39ah batteries.
Cheers
Rob
 
Also, should I use a 24V solar panel. I had presumed so, but thought I would ask anyway,
Thanks
Rob
 
I have a friend who needs to charge 2 batteries (one for CPAP one for telescopes). He got this and runs it off a single 350w panel. He says it works great.


The remote meter, while hideously expensive, it absolutely a must to get too.
 
Last edited:
I will be charging two lithium ion 24V39ah batteries
...
Also, should I use a 24V solar panel
Are they Li-Ion or LiFePO4 or Li-Po or another lithium?
Some are easier than others to find solar chargers that handle particular battery chemistries.
And no, a 24v panel is NOT what you want to charge a 24v battery. That fallacy came about when idiots started recommending hooking up a "24v panel" directly to a 24v battery to charge it. Without controlling the charging, like with a charge controller.

Find a big cheap panel on craigslist. Then find a charge controller that accepts the voltage and charges your particular battery(s).
 
They are Li-ion. I had a 12V panel from a previous project and tried to use that with a new lithium ion controller I purchased but I have been told it will only work with a 24V or larger panel. This have prompted my question if a single panel can be used in conjunction with a a double solar controller or two separate solar controllers to charge two separate batteries. lithium ion batteries limit my choice of controller.
 
I do not know much about charging Li-ion.
Find a charger(s) that know how to charge this chemistry and voltage (24v).
From there, the charger will have an input voltage range. For MPPT shoot for a panel(s) near the upper end of max input voltage. For PWM, shoot for something about 25% above your battery voltage (someone correct me if there is a better number here!)

And big cheap panels can normally be found on craigslist or eBay. Just stay within input voltage and input amps of your SCC of choice. If you find some and want a sanity check, post links, someone can likely help.
 
Anyone with input. If you can run two controllers from a single panel, too two separate batteries. Sorry, we got a bit off topic
 
Back
Top