I have been e-biking for a few years, and find myself in some exciting projects such as Solar Muscle Electric Vehicle design, and Redundant Open Source Battery Standard the later is presented here: http://prezi.com/qibqej3sqqy1/open-source-battery/ I have been researching on 'conventional' chargers and BMS and you notice asking me around here about Voltage Ranges and PWM spectrum motor drivers and such... I also love to know more about what you found with those batteries? On 10/17/14, RussellMc wrote: > What? > No users of Lithium Ferro Phosphate "12V" batteries? > Winston / Sinopoly / Thundersky / CAL / GBS / GWL / BYD / A123 ... > > No ebikers / mobile homes / self sufficiency ... aficionados? > > LiFePO4 is more cost effective whole-of-life than lead acid. > Knowing how to optimise this is my interest. > > Nobody else playing this game? > > > Russell > > > On 14 October 2014 03:25, RussellMc wrote: > >> Short: >> >> I need to become proficient in the care and feeding and optimal use of >> LiFePO4/ LiFeYPO4 batteries in the 40 - 400 Ah (maybe more) range. >> This is mainly a notification that I'm delving into this area and an >> invitation to anyone who knows anything on the subject or who can just >> tell >> an excessively interesting story to comment. >> >> As I know more I'll comment on what I learn if it seems useful. >> >> Initial 'playthings' are 2 x Sinopoly (son of Thundersky) 12V, 40 Ah >> LiFePO4 or LiFeYPO4 depending which blurb you read. >> >> _________________ >> >> More ... >> >> As part of a project I have just acquired two Simopoly brand 12V nominal= , >> 40 Ah LifePO4 (of LiFeYPO4) batteries. >> Each of these has 4 x 3.2V cells joined by nostalgia invoking cell to >> cell >> straps with bolt on busbars and the 4 cells are strapped together. >> Thusly http://images.trademe.co.nz/photoserver/full/242923341.jpg >> >> I could have bought similarly specified "Winston" LiFePO4 for only >> slightly more but various factors (including external cell terminal >> access >> on Sinopoly to allow balance checking and rebalancing) bised me towards >> SP >> for 1st off use. >> >> These will be used as a 24V 40 Ah battery with a small grid tied >> inverter >> and a 250 Watt 30VDC PV panel as a testbed for "related activities". >> A DIY MPPT solar controller may happen or the recent kickstarter offerin= g >> may be acquired. Numerous commercial offerings exist but most don't allo= w >> flexibility of battery management and monitoring that I need to learn >> what >> I need to know. >> >> My aim is to learn how to optimise some mix of whole of life battery >> capacity / battery lifetime / cost of energy storage / other. >> Other is always a problem. >> >> I'll be glancing briefly at the Suzuki LEAF LiIon cells which at very >> high >> cycle lives - although they had some early problems (as one does). >> >> There are various LiFePO4 management guidelines available from various >> manufacturers - with the usual level of contradiction one learns to >> expect, >> and uncertainty as just what is inside a given battery. >> different enough measurable characteristics to raise questions, and a lo= t >> more. (eg Winston and Sinopoly both derived from Thundersky but Winston >> have claimed a substantial jump in cycle lifetime relatively recently an= d >> have a higher charhging voltage requirement than Sinopoly. (Winston >> charge >> specs look almost like a LiIon being run in a modest way. Not what they >> claim and I'm far from knowing enough yet to be able to tell.) >> >> While small cell LiFePO4 charging is only somewhat puzzling (with some >> major variations from LiIon), advice of larger cells suggests a much mor= e >> lead-acid type approach with recommendations for bulk, absorption and >> float >> cycles, dire warnings against exceeding various DOD limits, reductions i= n >> cycle life with DOD from some suppliers that contradict those from other= s >> and much much more. >> >> There is a large amount of widely variable material on the ee blogs - e >> scooters, electric cars, motor homes, off grid community and more. >> >> What fun / agh! >> >> That should do to start >> >> >> >> Russell >> >> >> >> >> . >> >> >> >> >> >> >> >> >> >> >> >> >> Winston & Sinopoly both derived from Thundersky who may still exist as >> well, there's >> CALB, >> GBS, >> GWL >> Headway, >> Lightning Nano (26650 cells), >> A123 (18650 cells), >> LiFebat, >> and then there's BYD. >> >> BYD SHOULD be the 600 pound gorilla but may or may not have accessible >> product. >> >> Comparison of Sinopoly, Winston, CALB, GBS, Headway >> If you believed this you might buy Winston. >> I bought Sinopoly to start and am not yet aware that it was a bad choice >> :-). >> >> http://auto-elektryczne.com/images/LiFePO4-battery-EV/LiFePO4-battery-pr= ice-parameter-Sinopoly-Winston-CALB-GBS-Headway.pdf >> >> >> >> >> >> > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 Tobias Gogolin Tel. D1 (49) 0151 5187 5210 Tel. D2 (49) 0152 0839 5060 skype: moontogo messenger: usertogo@hotmail.com You develop Sustainable Ranch Technology at http://tech.groups.yahoo.com/group/SURA-TECH an Open Source Electric Motor/Alternator at http://groups.yahoo.com/group/Performance_Axial_Flux and an Open Source Motor Controller at http://groups.yahoo.com/group/GoBox --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .