Hi Tom; Each battery consists of 7 pack of 16 Panasonic CGR 1865D batteries making up a 48V system from what I understand from Panasonic 1.5 kWh. The Panasonic tech mentioned he knew of the firm and gave me the name of one if the tech officers. I'm going to look him up and see if I can get some info from him. Going to purchase a 48V charger and test each battery to see if it hold a charge. Thank you for your input.
Gary Rochlin / Managing Partner Blue Sky Energy [email protected] 310.422.2908 -----Original Message----- From: RE-wrenches [mailto:[email protected]] On Behalf Of Tom Ruscitti Sent: Saturday, February 10, 2018 12:16 PM To: [email protected] Subject: Re: [RE-wrenches] Older iCel System Lithium Ion Batteries (Steve Higgins) Some of my non-solar consulting involves test engineering for lithium ion materials development. I'm no expert but I do get to work with folks developing and testing cells and sit in on industry training and conferences now and then. I would discourage trying the jump start described here without direct guidance from the cell / battery manufacturer and a properly operating BMS. Li-ion batteries can be much less tolerant to over-charge and over-discharge than the lead acid we're used to working with in the solar business. Li-ion batteries require a strictly enforced minimum cutoff voltage. For example, the discharge cutoff for one recent client's battery is spec'd at 2.5V per cell. There can be damage to the anode If voltage falls below that. Also, if you try the jump-start on compromised packs with no BMS, different cells will charge at different rates due to differing internal resistance (one function of BMS is cell balancing). Over-charging can result in permanent capacity loss and also electrode damage. Depending on the chemistry this sort of damage can increase the risk of thermal events. I've heard that some BMS will prevent recharging if the minimum cell voltage limit has been busted, but no first hand experience myself. If you do a web search on "lithium ion damage over discharge" you'll see plenty of discussion. I tried to find specs on the iCel system but didn't find anything useful. be careful, Tom -- Tom Ruscitti Senior Engineer Taitem Engineering, PC 110 S. Albany Street, Ithaca, NY 14850 Mobile: (607) 220-7022 www.taitem.com _______________________________________________ List sponsored by Redwood Alliance List Address: [email protected] Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/[email protected]/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org _______________________________________________ List sponsored by Redwood Alliance List Address: [email protected] Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/[email protected]/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
