[metallica]

Originally Posted by thingstodo

Hi! Welcome to the forum!

I don't recall a BMS that Paul has designed. He has designed a 500Amp DC controller, a 1200Amp DC Controller, a 1000Amp AC Controller, a Resolver to Encoder converter board, and a DC/DC converter board .. that I know of.

I would suggest using a BMS that has a good track record, of course. The Leaf BMS is good at monitoring from what I read. I have not heard much about the balancing for the Leaf BMS. The Tesla BMS also has a good track record.

Are you recycling surplus batteries? Or building your own? For your first build I would suggest recycling. It simplifies things and you get results a bit quicker ... if you have the room in your vehicle for pre-built packs.

To talk to the boards in each Leaf module, Woltronix has a 'Leaf Pack sniffer 2' that I have read good things about.

For Tesla modules, EVTV has a board that will talk, as master, to the BMS in each Tesla pack.

Those are the most cost effective solutions that I know about.

I don't use a BMS - I bottom balanced my LiFePO4 pack and manually check the cells every 6 months or so, when I've run the pack low. The recycled cells have been rock solid.

My Leaf cells ... I foolishly damaged the boards while taking the pack apart. So I don't have an operable harness or the monitoring portions ... I check them about once a month. The controller on my Polaris Ranger EV won't start up below 42V. That's about 3V per cell. I didn't bottom balance the pack, I top balanced it so that all of the cells hit 4.1V at about the same time.
The voltage on the pack is not as stiff as the LiFePO4 cells, so when the Polaris shuts down, the cell voltage bounces back to about 45V. None of the cells is below 3V when I have let them cool down, before putting them on the charger.

But I'm just a hobbyist. I don't have a highway-capable vehicle running

Disclaimer: I am not affiliated anyone mentioned:
- Paul and Sabrina, I am a happy long-time customer
- Woltronix, I watch and enjoy his videos but have never purchased anything from him
- EVTV, I went to EVCON one year, and am a satisfied, long-term customer

Hello everyone,

Thanks for your welcome, and for your answers Freebeard and Thingstodo, it's very nice of you to have taken time to inform me. I realize that I was wrong when I talked about BMS. I mixed the names, but I was really thinking about engine controllers . I still have a little difficulty with the names of the different components...
But anyway, I read EVTV's opinion on BMS and I will remember that when I have to decide on a system to manage the charge of my batteries, this point deserves to be carefully thought out.

I am interested in electric vehicles for some time, but it is only in the last few weeks that I have been trying to gather information in order to establish the feasibility of a concrete realization (retrofit gasoline -> electric).
One point in particular seems difficult to decide: is it better to opt for a DC motor ? or synchronous AC ? or asynchronous AC ?...

In the current state of my knowledge, and from my first research on the subject, I will be tempted to opt for an asynchronous AC motor, and I saw that Paul & Sabrina have developed one.

So I would be interested to have access to the plans of this controller, as well as to the list of materials and components necessary for its realization. And also have an order of magnitude of its cost price, if anyone has this information.

And if one of you has an opinion or advice on the choice of the type of engine (DC, AC ...) this will interest me a lot too