How to charge HV batteries off car?

[Dan--T]

Hi, this is probably a newby question,. But what is the simplest way to charge HV automotive batteries up when they're not connected to the car?

I want to use my Lexus hybrid battery pack as a test battery to get things moving but I need to charge it up first,. And I guess I'll need to do the same once I have purchased my proper battery.

What is the recommended method?
(Please bear in mind I am not an electrical engineer so can't knock something up using a Prius inverter and some copper wire)

Thanks
Dan

[ZooKeeper]

For a hybrid pack, especially Toyota/Lexus ones, my suggestion would be one module at a time while secured in their case.

[Isaac96]

As ZooKeeper said. You can either use a proper charger or just a simple lab power supply - those have both current and voltage control so they charge batteries safely, also they're generally useful for EV conversion work.

[ZooKeeper]

As ZooKeeper said. You can either use a proper charger or just a simple lab power supply - those have both current and voltage control so they charge batteries safely, also they're generally useful for EV conversion work.

Yea, I know... so useful I am amassing a collection of them

[arber333]

Hi, this is probably a newby question,. But what is the simplest way to charge HV automotive batteries up when they're not connected to the car?

I want to use my Lexus hybrid battery pack as a test battery to get things moving but I need to charge it up first,. And I guess I'll need to do the same once I have purchased my proper battery.

What is the recommended method?
(Please bear in mind I am not an electrical engineer so can't knock something up using a Prius inverter and some copper wire)

Thanks
Dan

See here is a hard core method, but it works for every kind of automotive battery you can imagine .
https://leafdriveblog.wordpress.com/202 ... r-charger/
You can get a smaller version autotransformer for single phase connection and it will work up to 300Vdc or so.

If you dont need to have a fast charging then i recommend you buy a simple PSU for voltage you need to get battery to.

[rstevens81]

If they are in simple modules you can charge each module by themselves with a cheap lion charger from China land (if you open them up you can change the charge point voltage)
I did this 12 at a time to 3.75volts (45v) to put my modules into a storage state. I also monitored the BMS to be extra safe.

[Dan--T]

Ok, I ideally didn't want to have to split open the battery pack but if that's the best/ only feasible way to do it I can.

So I think each lexus cell is 7.2v,. So I just need to buy a power supply capable of over 7.2v and do them all one at a time?

[ZooKeeper]

So I think each lexus cell is 7.2v,. So I just need to buy a power supply capable of over 7.2v and do them all one at a time?

The modules are wired in series, the only way to do them all at once @ 7.2v is to turn every other one around so all the (-) & (+) terminals are on the same side.

[RetroZero]

What about the prius gen 2 Inverter as charger? There's a thread and quite some work done. Needs some fine tuning and testing from what I understand. I hope to get into that part pretty soon as I too have a hybrid pack that needs recharging. If I understand correctly, if there is no bms, current and voltage has to be real low as the weakest modules are going to take most of the first phase of charging.

[marcexec]

If you have to buy, I can recommend Meanwell LED power supplies. They come in various voltages and power levels and are current and voltage adjustable. I run a pair of waterproof HLGs to charge my bike overnight without issues (after switching to waterproof...).

[Dxtawise]

I think you could use a bunch of LED power supplies connected in series for this job.

[r1ckyb0nd]

Dan-t,

Where you successful in using the battery pack on the bench?
I am looking to do the same.

[arber333]

Dan-t,

Where you successful in using the battery pack on the bench?
I am looking to do the same.

I have one Chevy Volt pack on the floor for my HV test source. It works great for years now. I also use one Mitsu Outlander OBC/DCDC. However i need to be careful here as i dont have liquid cooling connected. I only have water in charger and hose looped between ports to have some thermal mass.
I charge slow at some 3A => 1kW.

3PH autotransformer setup i use as quick charger in case if all my chargers would somehow fail or i would really need to charge quickly....

[r1ckyb0nd]

Can you share how you connect to the hv battery and any documentation on how you (if you do) control the BMS?

[arber333]

Can you share how you connect to the hv battery and any documentation on how you (if you do) control the BMS?

Its rather complicated.
I used simpBMS connected to Ampera OEM BMS. It was not much, only CAN lines and power supply. But in the end i removed simpBMS in favour of Hanzor BMS because i could read 12S packs via Bluetooth and for SimpBMS i would have to have serial connected.
Generaly i made simple connections from cell tabs to screw terminals. From there i can use whatever connectors and BMS i like.
Lately i experimented a lot with ZEVA BMS...
viewtopic.php?p=78097#p78097

Last week i made changes in my workshop and now i will use Volt gen2 battery. Probably i will use ZEVA BMS. If you like i can post my assembly here.

[r1ckyb0nd]

Yes please