Sunday, June 8, 2014

Out with the old...

I've been really enjoying the ElectroJeep with its new LiFePO4 cells.  So much so, that I decided it was time for the Volt914 to get the same treatment.  The AGM batteries are now nearly 5 years old, and their capacity is significantly reduced.  I plan on putting 68 cells in so the nominal voltage level will be 218V, roughly the same as the 216V nominal of the AGM batteries.  The cells arrived this week - CA100FI cells, 100Ah LiFePO4:


I purchased 75 of them to allow for a 10% margin of failure.  Also purchased were 75 of Clean Power Auto's MiniBMS modules and the associated head-end controller, as well as an Android EV Dashboard from Electric Motor Werks.  The ElectroJeep has both those systems, and they are working very well.

It was rainy yesterday, so instead of doing yard work, I pulled the old AGM batteries.  Here are all the old batteries, stacked up behind the car:


I discovered significant water damage after pulling the batteries.  First, the battery warmers in the rear box were destroyed by water (they were still moist even though the car has been in the garage over a month now):


Second, water has somehow gotten into the front compartment.  I suspect this ended up worse than it could have been due to previous battery acid spills:


Sigh.  I'll fix it real good this time!  In the meantime, here is the layout I'm working toward with the new cells:


I'm going to make sure that the rear box is completely water-tight.  I don't want a repeat of the water damage.