I am surprised at people wanting an extremely large balancing current as that should never be needed unless your cells are either defective (too high self-discharge in some cells) or you are drawing current at inappropriate places (tapping the pack). As an example, the Leaf BMS has 10 mA (0.01 Amp) balancing current by using 430 Ohm balancing resistors. All 96 series cells are only connected to the BMS which apparently is guaranteed to draw extremely low current (everything is designed for very low current in their BMS, even the voltage reference works with microAmps of power supply) and the cell quality is apparently so good that their self-discharge does not vary enough to need more than this extremely low current.
There may be reasons to have a large balancing current, but they escape me. BTW, even though the Leaf BMS is part of the vehicle, it is self-contained in the battery box with only OBD coming out for status and it works and balances stand-alone as long as all 24 BMS front end chips are powered (4 cells per chip). With the (free) Leaf Spy you can monitor the BMS stand-alone, as long as you connect a Bluetooth ELM327 OBD interface. There is a way to use the BMS on anything from 48 to 96 cell packs, because the BMS has opto-isolation mid-pack, so you can overlap the BMS inputs if you have less than 96 cells (but at least 48 cells). The only thing you lose is the ability to break the pack midsection, unless you add another opto coupler in the RS232 data line that daisy-chains all front ends together. Regards, Cor van de Water Chief Scientist Proxim Wireless office +1 408 383 7626 Skype: cor_van_de_water XoIP +31 87 784 1130 private: cvandewater.info http://www.proxim.com This email message (including any attachments) contains confidential and proprietary information of Proxim Wireless Corporation. If you received this message in error, please delete it and notify the sender. Any unauthorized use, disclosure, distribution, or copying of any part of this message is prohibited. -----Original Message----- From: EV [mailto:[email protected]] On Behalf Of ken via EV Sent: Wednesday, July 27, 2016 11:02 PM To: paul dove; Electric Vehicle Discussion List Subject: [EVDL] 24 cell BMS I haven't see the prices yet but I see this as a Advanced version of cell log. with very good features. Smart Balancer & BMS series http://www.chargery.com/BMS24.asp it balances at 1.5 amps.!! they have other smaller cells version also. _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
