72VDC Lion (NOT LiFePO4) 4kW batteries on tap, looking for a solar solution to charge them.

[wruehl]

Hello,
Through my misadventures I have come to own several MetaCycle Lithium Ion batteries that I thought would make a pretty sweet little portable solar system. Hacking the charge contactor on the batteries is pretty straight forward, the interface is very simple. These batteries have a pretty capable BMS and I want to leave that intact and actually use it to protect the cells. What I'm looking for is a decent solar charge controller that can be setup to mimic the charger that shipped with the bikes. Same voltage cutouts, high and low. Equipment for a 72VDC nominal battery gets a bit sparse. I'm thinking 2000W of panel configured to match the input voltage of the charge controller, I just need a decent MPPT charge controller that can be setup for true Li Ion cells. Any thoughts? Suggestions?
Once that is solved a decent pure sine inverter would be great as well. Again 72VDC nominal input. 3000W 120VAC continuous would be cool. 2000W would work as well.

 

[OzSolar]

Welcome to the forum! Sounds like a fun project.

Take a look at the Midnite Classic 200 and Morningstar TriStar (I think that's what they are called). I know they publish some details about about higher than 48v nominal batteries. Hope that helps!

 

[wruehl]

Welcome to the forum! Sounds like a fun project.

Take a look at the Midnite Classic 200 and Morningstar TriStar (I think that's what they are called). I know they publish some details about about higher than 48v nominal batteries. Hope that helps!

That first one looks promising! Thank you!

 

[wruehl]

Just saw this too! Guess I need to get that Arduino talking to those batteries! Wicked!

https://www.amazon.com/3300W-Invert...1711771162&sprefix=72VDC+,aps,145&sr=8-4&th=1

 

[Andrewr05]

Finding an inverter to run off of those batteries is going to be very easy.

But finding a charge controller that can handle 72V is going to be very difficult, I'm running into the same problems myself with my 36V li-ion battery banks.

 

[rhino]

A Morningstar Genstar charge controller goes up to a maximum of 72V which I assume is slightly too low?

 

[Rocketman]

A business near where I used to live “electric car parts.com”, may have a lead on one. They have 12 to 48v mppt’s and 96v to 220v mppt’s.

(Yea can you imagine a 220v dc lithium battery bank! - wow!)

The owner is a really cool guy - met him once when I got eight 25ah cells for a smaller battery.

They special order lots of big things.

Good Luck

 

[pollenface]

MakeSkyBlue?

72V 30A MPPT Solar Charge Controller for 2200W PV Solar Panels

72V 30A MPPT Solar Charge Controller 100% MPPT controller Intelligent Maximum PowerPoint Tracking technology Built-in DSP controller with high performance Three-stage charging optimizes battery performance Multi-function LCDs Output limited current protection Overcharge protection...

makeskyblue.com

 

[OzSolar]

A Morningstar Genstar charge controller goes up to a maximum of 72V which I assume is slightly too low

You're probably correct, I've only glanced at the data sheets and not dug into the manual to find the exact details.

 

[KITROBASKIN]

Not trying to be an expert here but suggest you take a look at the AC charger that is used to recharge your battery packs. If it is like my 72V ebike pack, it is putting out 85V.

Thinking that high voltage charge controller is going to be expensive?

Not sure of your setup but if you have a system that is already functioning, with AC power available, one option is to charge those ebike packs with the charger meant for them, then using a Solar charge controller rated for at least 100V to use that power from the ebike packs elsewhere. Won’t win any efficiency awards but will get you some use from those packs?

 

[HarryN]

Finding an inverter to run off of those batteries is going to be very easy.

But finding a charge controller that can handle 72V is going to be very difficult, I'm running into the same problems myself with my 36V li-ion battery banks.

For some reason, I think that Bogart PWM solar controller can actually handle 36 volts, even though it isn't really mentioned much. They are pretty responsive to inquiry.

As mentioned above, several of the midnight solar controllers are rated for 12 - 72 volt.