60 MPH

After work at midnight I decided to finally find out the "performance" figures for the Electric Booger on the way home. Not exactly accurate as I was looking down at a stopwatch while I accelerated (really safe, I know!), but still, ball park figures to get an idea.

0-30 mph: 12 sec
0-40 mph: 22 sec
0-50 mph: 35 sec
0-60 mph: 55 sec

THAT'S RIGHT! 60 MPH IN A 72V EV!

It probably would have gone faster, but I didn't want my little motor to turn into molten lava, especially with the big hill I still had to climb on the way home.

Almost A Breakdown

It all started when my Kill A Watt stopped working. This is the device that measures my power consumption when I am charging. I also use it to verify that all of my chargers are working by the amount of power being consumed when I first plug it in. Generally, this is 1020-1070W after a commute. So I have been going without it for the last week. I have a good idea of when it is charged anyway, so I figured it wouldn't hurt to go without it until a replacement arrives.

Last night on my way home from work at midnight I started going up the one kilometer long hill when I noticed that the system voltage was lower than normal - 65V instead of the normal 68V at full throttle. So I reached over, grabbed my battery monitors and plugged them it. I gasped at what I saw: five pairs of batteries at a normal 11.5V and one pair at 5.5V! For those who don't know, anything under 10.5V for any amount of time is battery murder territory.

I feather footed it the rest of the way home, keeping the weak pair above 6V. At home I tinkered around for a bit and soon realized that one of my chargers was not charging. It turned out to be a fuse, which I replaced and it worked again.

The scary part was that I had been noticing the car was a little bit weaker the last few days, but I just attributed it to the colder weather. I really have no idea how long the one charger wasn't working and I had a bad feeling that I had murdered one pair of batteries.

I charged the pack over night and today during the day and the heavily discharged pair took 14-1/2 hours to charge. Normal is three hours if I fully charge after a drive home from work. I then split this pair and let them sit all day so I could check resting voltage to detect any internal shorts or weird self-discharging. They both rest at 13.84-13.88V, so it appears that they may live after all.

I will definitely be more careful to make sure all chargers are turning on from now on, at least until the new Kill A Watt arrives.

No News Is Good News

Nothing to report. Everything is working good. Drive to work...plug it in. Drive home...plug it in.

I have been meaning to double check all the battery connections to make sure they are tight - maybe this week yet. I would hate to have a bad connection a scorch a terminal.

My accessory battery charger works great.

My traction pack chargers work great.

My dual controllers work great.

My undersized, poor little SEPEX motor hasn't gone up in smoke yet.

1589 km (987 miles) on electricity so far....

What else can I say?

I can now plug it in and walk away

I have been using my new accessory battery charger for a couple of weeks and I am proud to say that I can finally plug the car in and walk away.

My old accessory battery charger was a Schumacher SC-1200A. 12A/8A/2A. I had to turn it on manually every time I plugged in the car. Annoying. And it wouldn't [I]quite[/I] keep up with the traction pack chargers, meaning that if I did too many short charges or didn't do a long float charge once in a while, my accessory battery would fall slowly behind after a few days.

If you are going to charge an accessory battery with its own charger instead of using a DC-DC convertor (like most sane people do!), the trick is to give it a charger that chargers slightly quicker than the traction pack chargers.

So I tested the Schumacher. It turns out that the "2A" mode really outputs 1.3A. EEP. What a piece of junk. I tested my new $18.99 2A ATV/motorcycle maintainer (immediately after testing the Schumacher) and it outputs 2.3A. Much much better. This 2A maintainer does not require switching anything on, which is the real bonus and the main reason i bought this charger. Plus, once the battery is fully charged (14.4V) it switches to a float of 13.5V. Not even the Schumacher did that.

Needless to say my accessory battery has been much happier lately. I can tell by the tone of my vacuum pump and the normal speed of my windshield wipers.

Plug it in, walk away.

There is only ONE thing stopping me from doing this right now, and that is my accessory battery charger. It is a Schumacher charger that keeps the 12V accessory battery (the one that powers stuff like headlights, contactor, stereo, vacuum pump, heater fan, etc.) charged. Every time I plug my car in for charging, all the traction pack chargers turn on and hum away on their own, but I always have to go inside the car and push a button on this charger.

This bugs me. I want to be able to plug it in and walk away. So for weeks I have been [lightly] searching for a nice 2A microprocessor type charger and turns on by itself. I finally found one yesterday on eBay that fits the bill:

It is actually sold by a powersports retailer and it's meant for maintaining batteries in snowmobiles, motorcycles and ATVs. $18.99 with free shipping to my US mailbox. Not bad.

I just hope it actually outputs 2 amps all the way up to voltage cutoff. That's really all I need to keep my accessory battery charged. And if it doesn't put out enough current I guess I will end up with a nice charger to keep my motorcycle's battery happy all winter long.

Mazda Engines

I have been meaning to haul the engine that came out of the Electric Booger to the scrap bin at work for quite some time now. It has been on Craigslist since I removed it from the car but as soon as people know that it has 281,000 km on it, they quickly hang up.

I don't have a pickup truck and though I could easily borrow one from work, coordinating a helper to lift the engine into the back has proven to be a challenge. So I decided to draw some inspiration from the old Johnny Cash song, "One Piece At A Time":

I have been stripping down the 1.6L SOHC high-miler down and taking pieces to the scrap bin every day. And I am extremely impressed by how everything looks in this engine. The bearings are all like new and the bores all have lots of crosshatch.

I could have easily lifted it into the back of the Electric Booger without removing the oil pan, stiffener plate, crankshaft, rods and pistons, but what fun would that have been? Plus, I might hang a piston from my rear view mirror as sort of a gesture of cruel irony.

I had lots of fun dismantling this tiny tiny engine - probably because I am used to doing 15L diesels at work. Car engines are so cute in comparison!

Wiring Schematic

I finally got around to making a proper wiring schematic for the Electric Booger. I thought it would be a good idea in case I end up selling the car in the future. Chances are by then I will have forgotten how I wired the whole thing!