It's been way too long since I posted here....
Big news: I ordered lithium batteries from China. They should be in within 2 months. I am hoping to get 25 - 30 mile range once I have the new pack in.

Earthday festivities

I took the car up to KCC for their sustainability festival. Here is the news story which includes a couple of clips of the Metro:

Battery tests

One of the folks at DeltaQ (where my charger is from) was kind enough to forward me this battery testing procedure. I am going to try it out today:

- The battery packs health can be determined with these tests:

1) Charge pack until green LED is on solid, then wait a few (>2) hours and measure the voltage of each battery. Voltage level indicates state of charge. i.e. Lowest voltage indicates battery with lowest charge.

2) Drive car around for a while to drain the batteries a bit, then wait a few (>2) hours and measure the voltage of each battery. Voltage level now indicates a batteries capacity. i.e. Biggest voltage drop compared to readings taken in step one indicate which battery has the least capacity.

3)Load batteries by turning on heater or minimum throttle and measure the voltage of each battery. The drop in battery voltage indicates internal resistance. i.e. Battery with biggest voltage drop compared to readings taken in step two has the highest internal resistance.

Batteries with lowest charge/least capacity/highest resistance are the weakest ones and should be replaced if performance is subpar, however, replacing all batteries at once for matched performance always gives the best chance of extending the life of each battery.

Pretty Plates

I got all my ducks in a row and picked up my "ELECTRIC VEHICLE" plates.
I needed a new saftey inspection, the new weight certificate, and the paper from the DOT certifying the car as all electric. Went down to the satellite city hall and got set up. I wonder how many other cars in Oahu have these plates??

I got

Weighing in

As part of the registration process I needed to have my car weighed. Here I am at the Toledo scale. The other part of the process is a new safey inspection and a a document from the DOT stating that it has been verified as an electric vehicle. I have that document. Now all I need is safety inspection.

Inside, in the AC comfort you can see that she comes in at a very trim 1840 lb. Only 90 lbs heavier than what is shown on the registration (1750 lbs)

Longest trip

I went 27 miles on a charge, but I had to stop to let the batteries recover, and limped in at about 20 mph max speed. Seems like anything over 22 mies is pushing the limit. Otherwise everything is running good. I am working on a vacuum system for the brakes.

The stats

I created a spreadsheet to track the energy use of the Metro. It can be viewed here:
http://spreadsheets.google.com/ccc?key=pqkXLgw4FcoLQX9v1NgZjbQ&hl=en

What the.....

What you see here on the right is a relay. On the left is a 1000 ohm 10 watt resistor. It's wired so that when the key goes to the first position the circuit across the contactor is closed through the resistor. That way there is no sudden rush of current through the contactor when I turn the key to the second position. I did this because the contactor had stuck a couple of times.

I'm on the third charge cycle. After 21 miles my hydrometer read 1.185, which would normally be about 45% charge. This may be close. I could have up to about 9 KWH of capacity in my battery pack. I put 5.54 KWH of juice in on this cycle. That = .26 KWH/mile. I will try to go around 30 miles on the next charge, monitoring with the hydrometer, and see how it goes.

I'm figuring out the shifting. I'm driving mostly in 3rd, then at about 30 I can pull it out of gear and it slides easily into 5th.
It has good pick-up and is fun to drive.

How much per mile?

Here is my preliminary calculation;
I used a device called a "Kill-o-watt" to measure how much Juice came out of the wall.
After a full charge I drove 9 miles. Then I did another full charge. the meter said that I used 2.55 kilowatt hours.
My electric bill says I pay about 20 cents/kilowatt hour. So the 9 miles used about 51 cents.
So around 6 cents a mile.
If I got 40 miles/gallon at $3.30 gallon that would be 8.25 cents a mile. Not a huge difference.

Moving out

Saturday
We wanted to build a box for the rear batteries and install the on board chargers before the final move out. Here is the box open:
and closed:
Matt found a great place to install the on board charger on a plate at the front of the engine compartment.Can you see Matt's fingers, putting in one of the final bolts?

The Maiden voyage

Saturday

We have the batteries secured in the front and are preparing to wire the final cables.Looks like rush hour around the controller with all the wires and cables.
The safety recommendations are to place plywood over areas not being worked on to prevent accidental shorts.
Also to be safe, before the final wiring we put the car up on blocks: just in case something unpredictable happened.
OK, all wired up, everything double checked. Key in the ignition, turn the key: NOTHING. The contactor did not close the 72 volt circuit. We got out the volt meter and tested the current to the contactor. It had 12 volts. We had tested the contactor before installing, and it made a healthy click when wired to 12 volts. We are scratching our heads. We gave Wilderness EV a call, and were lucky to reach them on the weekend. They said to test the circuit with a light bulb. Luckily Matt had a light probe in his bag of tricks. We tested the wiring we were using and sure enough, not enough current to light the bulb. We then started testing other unused wires, until we found one that lit up the light probe nicely. We wired the contactor to the good wire.
Maiden Voage take 2: Key in the ignition, turn the key: volt gauge reads 72 volts. Put the transmission in 2nd gear, push on the accelerator pedal, the wheels turn. High fives!!
We take the blocks out clean up and get ready for the first drive.
Here we are breaking the bottle over the bow before it slides into it's first trip.
We climb in, buckle up. Turn the key, 72 volts on the meter. 2nd gear, let out on the emergency break. Push on the accelerator, and start gliding out of the carport in almost total silence. Our trip starts with a steep downhill. The brakes without the vacuum pump need a lot of force. Then a stop sign, total silence. Pull away smoothly. The controller is functioning nicely with the motor. We cruise around for about 5 minutes, on the uphill the Amp guage goes up to about 300 amps.
On flats about 50 to100 amps. We reverse it back into the car port. The reverse seems a little trickier to control.
I turn the key off. Still have 72 volts. uh oh! For some reason the contactor is not releasing the 72 volt circuit. We unplug it, still 72 volts. we take of one of the cables to break the circuit, and then remove the contactor. We test it and now it seems to work.
Well almost a completely successful test drive. I am contacting Wilderness EV to see if they have a solution for us.

Sunday:
We spent the morning getting the rear battery rack ready. We will construct a plywood box to go over these batteries.

Secure batteries

We used some threaded rod and various bits and pieces to secure batteries. On the right you can see the new battery for the 12 V system.
We were able to reuse this gromet to protect the wires where they go through the firewall towards the 3 batteries in the rear.

Moving right along

Saturday morning we jumped right in to more wiring.

This is the throttle box , which I just finished mounting on the left side of the engine compartment behind the battery rack on
We ran the 3 wires from the shunt to the guages through the fire wall. We used the same grommet as the other wires coming from the cabin. One of the wires will be connected to the negative side of the battery string.

This shows the wires coming from the throttle box (black and white) and one wire from the shunt(red/black).The next sequence shows us preparing the terminals.

Strip the cable and insert it into the terminal.
Place it in the crimping tool.
Pound it with a sledge hammer until the gauge on the tool shows it is far enough down.Heat shrink tubing applied.
Here you can see the cables for the motor installed on the controller.

What's under the hood

I have had a few people ask about what components I am using.
Most are from a kit from Wilderness EV:
1. ES-15A Series Motor 40 HP Peak - 12 HP Cont.
2. Alltrax 7245 (72 vdc/450 amp) controller
3. Adapter Plate
4. Shaft Coupler
5. 0-5k Throttle Box
6. Contactor - Kilovac EV200 (2000 amp rupture 200 amp cont.)
7. 0-150 VDC Volt Meter
8. 0-500 Amp Meter
9. Gauge Holder Bracket
10. 50mv - 500 Amp Shunt
11. 32 ft of #2/0 ga. Wire Cable
12. 12 - High Current Ring Terminals
13. 24-Battery Cable Terminals
14. Fuse - 500 amp slow blow
15. 12 Volt Battery Charger

From Canadian Electric Vehicles:
QuiQ™ 72 V Battery Charger

From Sam's Club
6 29-DC 12 volt lead acid batteries
1 small 12 volt deep cycle sealed lead acid battery

Donor Vehicle
93 Geo Metro 2 door

Batteries are in

Here are the new batteries still in the trunk of the Benz.

Don't they look prouder in an Electric Vehicle ? Putting some heat shrink tubing on a battery terminal.
Here is a before and after of the cable.

Controller goes in

We secured and wired the contrller shunt and contactor in place. We made bars of copper to wire them as we thought this would be more solid and compact. We wired the contactor to the coil wire so that it will get 12 volt current when the Key is switched on.



The batteries are ordered and will be ready for pickup on Monday.

Laying cable

On Sunday we put the final touches on the throttle by fabricating a part to hold the cable, images will follow soon. We then started to pull out the center console to see where we might run the cable to the rear batteries. Then we realized it was a bigger project than we realized, and there was allready a nice hole in the firewall we could use. After lunch we took the 2 free ends of the 2/0 cable and ran it under the carpet, and under the back seat into the trunk area where we will have 3 batteries. It went much quicker than we expected.
One other item we took care of was connecting 2 of the contacts on the motor that need to be connected. We hammered out flat one of the copper connectors, drilled new holes in it and bolted it down on the motor. one more little detail taken care of. To finish up we shared the nerd joke of the day: "We are getting down to the wire".

Devil is in the Details

On Thursday we looked at how we would put the guages in and made some final adjustments to the battery rack. The clearance between the rack and the motor mount plate was a little tight, so we ground some material off the mount plate. We also fixed the hood release, it needed to have a spring replaced.
On Saturday we finished the mounting of the plate that will hold the controller and we mounted the gauges in the dash and ran the wires for their illumination. We tapped into the dimmer control wires. Our first attempt gave us unintended results. When the dimmer was low the lights were bright, and visa versa. We had to change the wires we used, then it worked fine. We went nautical with the right hand gauge green (starboard) and the left hand gauge red (port).
Then some 2 sided tape to mount them in front of the old gas and temperature gauges. They are looking good!!