On 3 February 2014 21:00, James Cameron wrote: > > Source code for the 8051 EC for the XO-4 can be found here: > http://dev.laptop.org/git/users/rsmith/ec-cl4-mmp3/ Thanks. I had a wander through the source code files to see if I could find the end of charge parameters and "what happened next" for the LiFePo4 battery, but without success. It may be in there somewhere. I found code or comments for rate of charge, voltage for transition from CC to CV and voltage for low current trickling up of grossly undervoltage cells. What I was looking for was what decisions had been made on when to terminate CC phase and what voltage (if any) was then applied to the battery, and at what voltage charging would be reinitiated. I have it on what should be good authority (and *no *direct personal experience) that the majority of the Chinese solar LiFePO4 charging designs have been deficient in this area and have been grossly damaging LiFePO4 batteries in consequence. As OLPC has had LiFePO4 for some years and would presumably 'have noticed' if battery packs were grossly missing the 2000 cycle target I was interested to see what decisions had been made. It would be interesting to hear from the OLPC battery charging gurus re what decisions had been made for LiFePO4 en of charge termination and restart. It actually seems "simple enough" to get it right, but I do not (yet) have the in-field several year results that prove me correct. Presumably OLPC do, and in large volume. Russell --=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 .