Just replaced the traction battery with K2 Energy LFP26650P LiFePo4.

I need to figure out how to capture the data. I have just replaced the traction battery with one I've fashioned together with K2 Energy LFP26650P LiFePo4 cells. The batteries were free. A local junk/scrap dealer came across these and didn't know what to do with them and listed them on facebook marketplace for free. I wasn't the first to respond but I was the first to show up at their warehouse. I ended up with 17 military modules plus one master control unit. Each module has two banks of 80 batteries in 20s4p configuration, 64V each 10.2 amp hours. At first I took one of the battery banks apart... lots of sparks! After the difficulty of trying to separate the spot welded batteries I had to think how I could use the batteries in their existing configuration. I used 3 and a half banks, connecting the Prius voltage monitoring harness in correct sequential order every fifth row. 16V nominal with 10.4 amp hours. Total of 280 cells. Car runs! Now to see how it's going to progress... The logic for replacing the battery seems fairly straightforward, however, I have zero knowledge of how the vehicles computers will adapt to this battery. Technically, it's the same technology in a different format than project lithium battery. Crude implementation on my part, but functioning. I'm tempted to build another and go a bit further; place the harness leads every 6th row instead... for a module nominal voltage of 19.2V... Batteries are powerful, what will the ECU's do with it? I do not have the cables that go with the original modules but am thinking of attempting to utilize the master control module with 7 of the the modules as a power wall. Lot's to keep me occupied... much needed after losing my son to suicide 3 years ago. 2008 Prius touring edition. I have a 2010 with solar roof that will remain stock unless I find the lithium battery satisfactory.

 

So I had become quite pleased with the LFP battery crudely implemented and needed to make it a more permanent installation that could fit under the oem metal housing. Quite dicey as hv connections are very close to the metal case. I’m using adhesive backed thick barley paper directly on underside of housing over connection areas. It is a very tight fit. Air flow is a concern due to the tight welded configuration of the 26650 cells. I now have P0AA6 which can be cleared while driving, but after powering vehicle down it is necessary to ‘clear’ battery codes to get to READY even though no codes are showing. Something about isolation between high and low voltage systems. Due to physical limitations I moved where the safety plug connects to battery. Instead of between 4-5 it’s now between 10-11. Performance is noticeably reduced after this attempt at permanent install. Instead of ~41 mpg with stock Nimh I was getting 46-47. Also, I was seeing much higher amp draw on heavy acceleration compared to stock. Much reduced after fitting battery to metal compartment. I do think there is a ‘learning’ period required for the ECU to most effectively manage battery. I have thousands of these cells and would love to be able to successfully add more capacity in the storage area above spare tire. Looking at using a pelican style case in that space bolted to metal.