I have some BB600 batteries that I bought years ago and never used so I'm thinking of using them for an off-grid EV charging station (more in a future post) I used to have a copy of the maintenance manual for them, but I can't find it. Anyway, I have some notes that Saft recommended to use a constant current at their C/5 rate until they reach 1.6VPC (about 5 hours if fully discharged) and then reduce charge current to C/50, with no voltage limit, and continue for a time period equal to the bulk charging phase. Since these batteries are rated at 34AH, that would be approx 6.8A during bulk charging and 0.68 for the finishing charge.
I've seen some old posts on here that say, to reduce water consuption, limit the voltage in the first stage to 1.4-1.45VPC and just measure current out/in and return 100% of the amp hours during bulk bulk/taper charging stage and then an additional 10% during the finishing charge. Either way you return 110% of the amp hours discharged. Since this is going to be a solar charger I can't guarantee constant voltage/current, so I'm thinking I'll just go with best effort, measure AH removed and return 100% AH during the bulk charging phase and then an additional 10% during the finish stage. I'll keep track of estimated SoC so if I can't return 110% on a given day I can make up for it later, perhaps do an addition 10% "equalization" charge periodically. For those that have used Saft NiCads, does this sound like a good plan or do you have any suggestions for a better algorithm? Thanks, Pete. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20201125/c5c9c230/attachment.html> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/index.html INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)