New consulting relationship with GreenTecAuto begins
What actually goes wrong with the batteries????
A look at todays Hybrid and EV battery packs
Battery packs exposed
2006 and up civic packs
Lead acid battery failure examined
Testing the sticks at the cell level
MaxIMA stick full discharge
Bumblebee battery replacements for the stock subpacks
Inside the cells
Seprating the cells for reuse
How it is wired
PTC strips exposed
The PTC thermistors
Battery current sensor
Inside the 100A semiconductor battery pack fuse
Did it again for the last time
A bad Prius subpack explored and fixed????
Rebalancing the Insight battery?
Insight battery
Insight Battery switching/current monitoring
The battery controller
Prius battery pack
State Of Charge (SOC) determination with NIMH batteries
Battery pack monitoring
What happens to a Prius subpack when you overcharge it?
Keeping Warm In New England
Plugging into the SUN
Making a small solar concentrator
Building MIMA and the plug in adapters
Converting a telephone truck to electric
DIY dual pulse Capacitor Discharge Spotwelder
Getting in shape while making electricity
Replacing gasoline with solar electric lawn equipment
What is Genesis One?
How to stop the aging process DIY
MIMA Install Day 2005 a Big Success!
Building a hybrid car grid charger
Tapping into the Wind
Expanding MIMA with the Distribution board ( users projects )

What happens to a Prius subpack when you overcharge it?

What happens to a Prius subpack when you overcharge it?
Opps! Cooked some prius subpacks

Well it happened again. I put my dual prius subpack on my 6A 75V solar panels for a quick recharge between the solar dish runs, and forgot it for several hours. When I finally remembered it, the black tape holding the subpacks together had nearly ripped apart and the cells swelled up with a lot of internal hydrogen pressure. Usually the subpacks are clamped tightly so they cannot swell, so they would vent the gas instead. I measured 140F between the packs, and submerged them in water to cool them.
Even after an overnight cool down, the subpacks were still swollen. I drilled six holes in two boards, to clear the locating tabs, so the clamping pressure would be uniform, and squeezed the subpacks together. Several hours of clamping, and the cells were back to normal shape, with no signs of any fluid venting.
I used the same packs to run my next canning run, and also to run a 30A 12V heater, and they seem to

Have been using the same dual pack in my lawn tractor for the last 2 years and they are working fine.
Some tough batteries for sure.