24s 15 amp lipo.....need a charger and BMS

[litespeed]

SO I've searched, read and now more confused than ever. I want convenience of simple charging for my bike. I do not want to separately or bulk charge 12 6s 5000mah packs so I started searching here, searching online and local for a 24s lipo BMS and a good quality charger that puts out 10 to 20 amps. I've wrote to a few Chinese companies that sell BMS and no response for a week now. I'd like to obviously have a full BMS and not just a LVC/HVC system. If anyone has bought a good working system that they could recommend then by all means please do so. I hate to be a beta tester or Guinea pig so hopefully someone has some recommendations for me. Same on the charger but figure I need to know the boundaries of the BMS (read charge rate!) before I buy a charger.

These are the places I found and that I have tried to contact,

http://bestechpower.com/888v24spcmbmspcbforli-ionli-polymerbatterypack/BMS-D138.html
http://www.e-chips.com.cn/English/En_ProductShow.asp?ArticleID=260
http://www.foundingpower.com/en/Products/Smart_BMS/2012081492.html
http://www.foundingpower.com/en/Products/Smart_BMS/2012072483.html
http://www.foundingpower.com/en/Products/Charger/20130201108.html
http://www.ebike-bmsbattery.com/dispro.php?id=159
http://www.szsmartec.com/EN/productsview.asp?PID=833

Thanks a bunch.

Tom

 

[litespeed]

Is there really no one here that uses a BMS and/or bulk charger?

Tom

 

[999zip999]

Two hp power supplies 24v 1000w. Two hyperion 1420 at 10a. each and balance charge. Or Two more hp 600 ect . power supplies more and their you go.
Plus alams set at 3.6v. ? Or cut off.

 

[999zip999]

I understamd you want to monitor all cells by number at all times and still look up and ride. Both things at once. Still I do need to know that one cell under Load. Yes that one cell. That one.

 

[mvly]

I would run lipo without BMS. But if you insist on BMS, I would look at cellman's lipo BMS. If you get a lipo charger then balance charging every other time or so or when it becomes unbalance should be sufficient. I have been running my lipo BMS free for a 1.5 years now and up to 255 charge cycles and no problems so far. Though some cells are harder to get to max during charging. But once balanced, they stay very close to each other.

 

[Peter Sternersson]

I am having the exakt same problem as you.

I am in the building phase of a 24S lipo configuration, and is looking for a similar solution as you.

24S BMS are hard to find, BMS that handle 100A continious is even harder. I have gotten around the amp problem by connecting by running current through the BMS only when charging, and also to power the controller (LYEN with a seperate low current control feed).
This way, the BMS controls and balances the charging, and if one cell is low during use, the low amp control current to the controller is cut off so you cant continue to drive and ruin your cells.

However, despite of this I still haven´t found a good 24S BMS for Lipo. I also have contacted several sellers on Alibaba and such, without any respons...

My best bet as of now is to use 2 12S BMS connected in series, they are more readily aviable in normal webshops and on ebay.

In my mind there should not be a problem to run the two BMS in series... I think...

 

[knighty]

I've been looking too, I think everyone here has at some point.. and there's no really good system out there yet :-(

even just charging a 24s pack without having to strip the pack down is tricky... (and or expensive)


I think I'm just going to buy 24 x single cell chargers, strip them all down and mount them in a box

might be a bit bulky but it'll be ok for at home in the garage... I can bulk charge if I need to charge away from home

 

[Peter Sternersson]

I have made a diagram of how I will connect up all the cells to 2 12S BMS, and splitting the pack with a swith to bulk charge the pack as 2 12S in parallell, using a BMS bulk charger at 50,8V.

I am planning to get Haiyen 4S Lipo packs and connect 6 of them into a 24S pack.

The best thing would of course be finding a 24S BMS, and gettig a charger with 100,8V output.... But where...

 

[circuit]

24s BMSs are not popular due to security concerns. Having many thin wires with different potentials going to one place is very unsafe. I've seen many fires caused by these wires...

 

[knighty]

http://www.bmsbattery.com will sell you a charger for whatever voltage you want if you email them

even with 2x12s BMS you should be able to bulk charge as one 24s pack ?

 

[litespeed]

Thanks for the thoughts, ideas and info, much appreciated.

Tom

 

[Peter Sternersson]

even with 2x12s BMS you should be able to bulk charge as one 24s pack ?

If you run all the discharge current through the BMS I think it is possible to charge 2x12S BMS with 100,8V. Not totally sure what happens if all the cells on one BMS are perfect in balance, and some cells on the other BMS aren´t, then the first BMS will shut down and no more charge current will flow through either BMS.

If you intend to do like me, and just let the control and charge current go through the BMS, then you have to break up ther pack into 2x12S and charge in parallell, or else it will continue to charge even if the first BMS cuts out. This is based on BMS boards that break the negative connection, not sure if there are other types...

I spent a few hours yesterday searching for 24S Lipo BMS, everywhere I could think of, but with no success. I´m actually thinking of going down to 20S now just because of that