Using high voltage batteries (for e-trikes) in a solar system?

[RighteousWeevil]

I drive a pedicab and travel with that to different events to make money. Ebike motors need to run high voltage batteries. I have an investment in 72v 50ah batteries and would prefer to use those rather than investing in an entirely separate voltage. I'm charging mine off shore power, using a Victron 48v | 500w inverter in conjunction with a 72v to 48v step down dc-dc converter (from AlieExpress.)

I'm worried that the stepdown converter isn't the best solution for this. They create a lot of wasted heat and inefficiency, right? I don't want anything to burn up or die while on the road, and I don't totally trust these alieexpress products. Does anyone have good recommendations for a better way to do this? Also, are there any good inverters that can straight up take 72v batteries? So glad to have this forum's expertise.

 

[HRTKD]

That's an oddball voltage. If you're going to use the converter, I would charge outside and have a fire extinguisher handy.

 

[Supervstech]

I drive a pedicab and travel with that to different events to make money. Ebike motors need to run high voltage batteries. I have an investment in 72v 50ah batteries and would prefer to use those rather than investing in an entirely separate voltage. I'm charging mine off shore power, using a Victron 48v | 500w inverter in conjunction with a 72v to 48v step down dc-dc converter (from AlieExpress.)

I'm worried that the stepdown converter isn't the best solution for this. They create a lot of wasted heat and inefficiency, right? I don't want anything to burn up or die while on the road, and I don't totally trust these alieexpress products. Does anyone have good recommendations for a better way to do this? Also, are there any good inverters that can straight up take 72v batteries? So glad to have this forum's expertise.

Ebike batteries are high discharge, lightweight batteries...
LiNMC most often, and they are very explody...
The charger is mostly a trickle charger.
However, 72V, 50Ah is a lot of battery! I wouldn't want it attached to a solar charge controller that could fill it during the day.

Best to stay with LFP 48V banks, and use existing inverters designed around it.

Can it be done? Sure...

Will it be EXPENSIVE? damn right... one off, or obscure stuff is often pricy.

 

[Vigo]

If you really want to power something with the 72v packs i would probably try to pick up a used UPS that uses a 72v battery architecture and then either power stuff with that directly, or use it to run a 48v charger into a larger, 48v system.

Looking up 72v ups got me a lot of listings for batteries which could be ‘traced’ back to the ups that uses them, or for example this silly stack of SLAs with jumpers in series to make a 72v pack, has the model numbers of some UPS’s that use 72v in the listing title. A bunch of searching along those lines should eventually lead you to a really cheap used UPS on ebay that will turn your 72v packs into some usable 120vac.
72v battery pack for ups