2004 Battery "Event" (plus other battery info)

On August 23, 2004, my Rav4EV had a "battery event." Nobody knows exactly why, but at 32% SOC, my car shut down after briefly showing a low module voltage in the 4V range. The battery ECU was initially swapped for a new one, and two modules were going to be replaced next. Although the suspect modules tested OK for capacity - after a day of sitting, my dealer's EV tech was not happy with how they responded. 

The vehicle left an error code that points to a failed battery ECU, but replacing the ECU by itself did not fix the problem either. Eventually the old ECU was put back in, and no batteries were changed out. The car was charged to 100% at least once/day for two sold weeks, and after my tech manually reset the zero and 100% levels of the pack - presto, the the car works again. In the end, nothing was replaced. Everything points to innacurately reported SOC.

Internal resistances

I rode my bicycle down to the dealer to snap some pictures and speak with my EV technician while my batteries were being checked out. I immediately found my car in the lot - it is now apparently ready for high water. This reminds me of the EV1 pictures after the packs were removed. Here is what the Rav looks like when it is 1000 pounds lighter. Should have higher cargo capacity now, huh?

And yes, for the sake of science, I even crawled under the car to take pictures of what few people (we hope!) will ever see.  This is where the batteries are supposed to be.

This is a closer shot of what you see up front that is usually obscured by the battery pack.

And looking rearward, this is where the air is sucked in from the quarter vents.

On the floor in the shop. Surrounded with "High Voltage - Caution" tape. I had to promise not to fall on it, or drop my camera in there.  :)

On the left are the two fans.  The picture below this one shows them in more detail. These are the fans that pull the air in through the louvered vents on the rear quarter panels. The vents that are now easily removable.

The battery fans.

One of Sean's packs in Kenya. Modules number 19 and 1 are fried.

My tech was kind enough to allow me to take more pictures after my first visit, so by request, I also took some pictures of the custom lift and battery support rack. First the lift.

This device follows the contours of the bottom of the pack, to allow full support across the pack. This support rack sits firmly on the black arms of the lift, as well as on the arms of a standard vehicle lift as seen here.

I again decided against licking the end of that orange cable coming off the front of the pack - tempting as it was.

The batteries are configured thusly (an S after the number signifies a temperature sensor). Here is a scan of the output of the Toyota handheld scanner from back in 2007.

Right Side
Service Prug
Left Side

Internal resistances of my batteries over time.

New pack in 2013: All of them are 5.5 except modules 8, 9, 12, and 13 these four are 5.75

One of Sean's packs in Kenya. Modules number 19 and 1 are fried.

Mark's pack dirty.

Mark's pack clean.


Video of Rav4EV pack being removed:

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