August 2009


Working hard on Analog Lithium BMS board.
– Using Toner Transfer process.
– Print reverse image on a LASER writer only.
– Iron or laminate to copper.
– Etch in Ferric Chloride.
– Drill holes
– Test
– Next version could have an Atmel processor.
– Pulsarprofx.com for Toner Transfer details.
– Trying out GBC H310 Laminator

Bought 30 more A123 Lithium cells
– Hand tested each one.
– They are used cells.
– Most tested at 95% capacity with a 35 amp load.
– Will retest at 5 amps to see what cut Peukert takes.
– Rotordesign.com/blog

HexaYurt Building
– Goal to have it half done by Monday or I quit building it and get a tent!
– Canvas K-Hinge makes for attaching all roof and wall panels together so tape is not needed.
– All panels are hinged to each other with canvas K-Hinge.
– Unit folds out in one continuous piece.
– between some panels a #10 zipper is sewn in so the joint won’t fold.
– Need some form of cooling.
– Spray bottle has been claimed to work inside Yurt for cooling.
– Rotordesign.com/bm

Purchased 8 Dolphin boards.
– Two needed repair.

Saturday Aug 29th, 2009 EAA Rally.

Move the SJEAA website!!!!

I finished testing all 30 of the used A123 cells. They were all about 2.18ah with a 35 amp load. I’ll retest a few of the cells at 10 amps to see how much of a cut Peukert is taking. The fan was helpful in cooling the cells down. As the cells warmed up the voltage would noticeably rise on each cell.

Here is the A123 cell charging fixture without any cells loaded.

Here is how I was discharging each A123 cell at 35 amps. That blue plastic clamp made this mundane testing go by more quickly.