New consulting relationship with GreenTecAuto begins
What actually goes wrong with the batteries????
Using the charger to run a deep discharge
Time to get serious about determining what actually fails in the sticks
A better way to test a full pack on the stick based level
What happens when you discharge completely?
Setting up to watch the sticks
First results
Recovery after the deep discharging.
More deep discharging.
Connecting to all the sticks with the multimeter test fixture
A graphical look at silver pack deep discharge 2
Testing a pack of new MaxIMA sticks with the multimeter test fixture
The next discharge after a regular plateau based recharge
Subpack 1
Subpack 2
Subpack 3
Subpack 4
Subpack 5
Subpack 6
Subpack 7
Subpack 8
Subpack 9
Subpack 10
Zap test of MP 10
Subpack 11
Subpack 12
Subpack 13
Subpack14
Subpack 15
Subpack 16
Subpack 17
Subpack 18
Subpack 19
Subpack 20
A look at todays Hybrid and EV battery packs
Battery packs exposed
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 )

A better way to test a full pack on the stick based level

A better way to test a full pack on the stick based level
A better way to test the subpacks

I have a bunch of sticks that are some where between good and bad, and need a way to quickly sort them.
I will be developing a stick level monitoring system down the road, but wanted something that I could make and get operational quickly yet have good precision.
I started with 20 Harbor frieght DVM's which I was able to buy for $3.99 each. The DVM's are microcomntroller based, and have pretty good repeatability, and have a small calibration pot inside that allows matching the meters down to the 0.01V level.
I tested one of them, and saw that it draws 0.9MA from the included 9V battery, and the meter stays accurate until the 9v battery volts drops below where the low battery warning level display comes on.
I made a plywood back plate, and used velcro on the backing plate, and rear of the meters so they can be easily removed for calibrating and battery replacement.
To make the connections to the batteries, I sliced some hard brass .02" thick into 3/4" X 2" strips.
I ponched 2 mounting holes in ach and bent them into right angles.
I used a 1/4" rod that was rounded in a drill press to indent each contact point so it has a male protrusion to capture the 6MM screw hole on each end of the sticks.
To allow free air cooling, I put two 1/4" strips of wood across the base so it holds the sticks off the base for better cooling.
I soldered jumpers between the terminals to put all 20 sticks in series.
I will make an adapter so the same meters can be connected to a pack that has not been opened, so they can do double duty.
Cost $90 so far.
Seems to work well