Minimum Voltage for EM3EV Battery?

[majornelson]

I've installed a MAC 10T, 6 FET Controller and 50v battery (50V 10.25Ah Samsung Pack - Cell Type: SDI-ICR18650-22P) from EM3EV on a Electra Townie. Really like the setup...

I've installed a volt meter on the kit to monitor the battery's charge (trying not to discharge too much). Does anyone know what is the minimum voltage is for the pack? Full charge looks to be about 58v.

I'm certain that this is obvious but I can't figure it out!

Thanks,

Lee

 

[melodious]

14s Li-Ion BMS from EM3EV.com

•Over-discharge protection Voltage, 2.75V
•Over-discharge recovery Voltage, 3.0V

14 x 2.75 = 38.5v
14 x 3.0 = 42.0v

I'm intelligently guessing (based on the fact that most of the useable capacity of Li-Ion is above 3.0v) that 42.0v is your magic number

edit: Also assuming your pack is an EM3EV pack based on 14s Li-Ion, NOT 13s Li-Ion like many "48v" packs.

 

[wesnewell]

Here's the spec sheet for them. I know people rave about these, but I wouldn't touch them. Sounds like a 14s pack, so I'd stop at 46-49V resting to prolong life. The spec sheet really tells you a lot if you understand it.
http://www.pollin.de/shop/downloads/D271149D.PDF

 

[docnjoj]

Hey Wes. Do you ever get pulled over by the cops for that bike. Those batteries stuck to the side would probably have someone here in Guantanamo. You got a cover?
otherDoc

 

[majornelson]

Thanks. Yes, I have the 14s and I think that 42v minimum makes sense. I'll send a note to Paul just to check...

My other bike has a CA and that convenient battery icon.

Thanks!

 

[wesnewell]

Hey Wes. Do you ever get pulled over by the cops for that bike. Those batteries stuck to the side would probably have someone here in Guantanamo. You got a cover?
otherDoc

I've been pulled over once at night, but it wasn't because of the motor or battery pack. It was because the cop was ignorant of state laws concerning lights required at night. I've never had one pull me over for speeding, since I don't speed. At least not where they've seen me. I ride by the police station all the time. Oh, no, I don't have a cover for it. Don't need or want one.

 

[Make More Pi]

I have these same batteries as well. I am setting up my CA. What Cell Chemistry do I select? I believe the battery chemistry on the ICR18650-22P is LiNiMnCoO2. It must discharge similar to one of the chemistries that can be selected on the CAV3 but which one?

 

[Russell]

I've installed a MAC 10T, 6 FET Controller and 50v battery (50V 10.25Ah Samsung Pack - Cell Type: SDI-ICR18650-22P) from EM3EV on a Electra Townie. Really like the setup...

I've installed a volt meter on the kit to monitor the battery's charge (trying not to discharge too much). Does anyone know what is the minimum voltage is for the pack? Full charge looks to be about 58v.

I'm certain that this is obvious but I can't figure it out!

Thanks,

Lee

What is the peak current for the controller? The more current you draw the more the voltage will sag and the less usable capacity you'll have. I just ran the numbers for my 13S4P 29E pack here;

http://endless-sphere.com/forums/viewtopic.php?f=4&t=62552#p942619

If you can find discharge curves for the 22P you can do the same.

A simpler answer however if you are running a 25A peak controller would be to stop when the resting voltage is about 49V. If you have one of cell_man's programmable controllers you might want to set the LVC to about 44V.

-R