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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hello Wrenches,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve been trying to think through how I can mate some lower cost charge controllers (prostar 15A 24v PWM units, or the new 30A Midnite solar Brat) to some 8s LiFePo battery banks.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>As I understand it, lithium batteries meant to be charged to around 3.65V per cell (29.2V for the 8 cell bank) and then the charge is terminated, not put into a float mode.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Assuming I use a PCM to protect the batteries, so that each cell has a balancing function and also over/under voltage protection. Would the battery bank accept a simple charge controller that in essence, charged to 3.65V/cell, then backed down to a float voltage that was lower than it’s resting voltage, say 3.3V/cell. In theory at that voltage, there would be little/no charge current going to the batteries. Or would the cells still take in a small amount of power at these voltages and start to overcharge/degrade?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Again, I’d plan to have a full PCM circuit protecting cells and balancing them, but I’d like to have a good way to charge the batteries with solar (right now I’m shooting for using a 72cell module and 24V nominal LiFePo battery stack, so maybe there is another way that I can use, but I’ve not decided to buy any batteries I am ok with accidently blowing up if I’m wrong<span style='font-family:Wingdings'>J</span>).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>With Regards,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Daniel Young, <o:p></o:p></p><p class=MsoNormal>NABCEP Certified PV Installation Professional<sup>TM</sup>: Cert #031508-90<o:p></o:p></p></div></body></html>