Tony's Free EV

What do you say when someone offers you a free EV?

What if it is 26 years old?

I assure you I never expected to enjoy owning a Geo Metro, but since it had been professionally converted into an EV becoming a Solectria Force, well maybe… However, this little vehicle has somehow wormed its way into my heart regardless of almost leaving me stranded twice while driving it. It only has a ~30 mile in-town range, and doesn't like hills or freeway speeds with its current battery pack (but is capable of both...for a little bit).

I first learned that these little cars existed when a fellow OEVA email list subscriber posted that he had a 1997 Solectria Force with less than 40k miles up for grabs at his house. The car had no batteries installed, and was missing most of the battery pack cables and arrangement foams. I was completely unaware of the history behind these things (read about it here on Wikipedia), so I emailed the owner about my interest and went to check it out.

When I arrived, the car was covered in moss and tree droppings. The original white paint was thoroughly coated in a green layer, so body condition was unknown but seemed structurally intact. It had been sitting for years, the then current owner had been driving it when one of the batteries in the pack gave out and left him on the side of the road. He removed them all with the intent to swap in a lithium pack, but never got around to it and had lost interest in the project. He just wanted someone to take it out of his driveway, and I agreed to do just that.

Got it home, and decided I would just drop some used (but still marginal-good in health) 12V lead-acid batteries in it that I had access to through my job and see if the drivetrain and electronics had survived the years of neglect. Bought all new cables and lugs to build the necessary connections to make the pack whole again, did some research on forums from a decade ago on how the pack was originally arranged, and got it all wired up on Christmas Eve. That very same day, my other vehicle died and went in for repairs, so this quickly became a do-or-don't drive situation! Fortunately, once I got the pack assembled and connected the old girl fired right up (for lack of a better term) and seemed like it was capable of powering itself down the road.

I tested the charger, and it was charging, slowly, but seemed to work and stopped charging when I expected it to with a full pack. Great success! Checked out all the lights and peripherals, and everything seemed to be in working order. Everything except the factory AH (amp-hour) counter, which is the only indicator of battery capacity in the cockpit. But who needs that, right? I was pleasantly surprised with the outcome of this build, I expected to have to do some further digging and repairs to get it road worthy. Not a bad turnout for what was currently only a ~$400 investment.

Emailing my insurance company to activate the policy for the car, I then took off to do a short test drive around the block. Not sure what I expected out of a 90s Geo Metro, but I think I had great expectations since it was an EV--all EVs are quick and snappy, fun to drive vehicles, right?! Well, this one drove like a Geo Metro, slow and steady. It would gently accelerate but was definitely not winning any drag races. Regenerative braking was clunky and the relay clicking was very obvious every time you let off the accelerator to enable the brake lights. Stark contrast to all my other EV ownership experiences. Still, I was able to drive it 5 miles and then do a pack evaluation back at home. No abnormalities noted, the batteries seemed to be fairly well balanced and holding up. No hot spots detected on the cables and no hot cells.

So, logically the following Monday I decided to take it on the 12 mile hike to work. Following my normal routine, I hopped on I-205 to I-84 and (attempted to) cruise in following the flow of traffic. Zero to 55 MPH was about 75 seconds...we didn't get to the speed limit much on that drive! Made it just over the river on the I-5 bridge, and noticed when I was merging onto I-405 I wasn't gaining speed. I ended up cruising on 405N to my exit at about 25 MPH in the slow lane, flashers on. Barely made it up the exit ramp, and crawled into work at just 2-3 MPH with the pedal to the floor. A win is a win though! Grabbed my DMM and did a quick static voltage comparison, had a few batteries that had dropped into the red and were going highly resistive. Perks of using mismatched batteries at varying states of health, I suppose.

Plugged it into 110V and let it sit all day. By the time I was ready to leave I was reading ~70% charged based on my best guess, looking at static voltages after I drove it a few hundred yards and let it stabilize for a few minutes. Took it nice and easy on the way home on side streets and had no issues.

Fast forward a year and a half later, and once again my primary car was down for upgrades (the good kind, woohoo!) and we had an OEVA meeting in Beaverton. Since my original adventure I had driven it to work maybe a dozen times and done many short trips with it around home, without issue. Usually I made a point of avoiding the highway since I knew the car wasn't a fan of it. I had swapped out some of the exterior bulbs to reduce the standby loads, and had great aspirations and plans for how to build a custom balancing BMS for the vehicle. I was also amassing lithium cells to do a lithium conversion...all great plans, but no action taken yet. I had replaced the wipers and the front tires as the rubber was heavily cracked; rears were done shortly before it was parked (it looked like, anyway). I had also had a detailer at work spend a couple days on it, so the car looked like a totally different vehicle.

So, I drove it to work that morning and plugged it in to charge for the day. When it was time to go, I meandered over to Burnside and began climbing...and climbing...and climbing...up over the hill, at about 25 mph to try and conserve power (no traffic behind me fortunately). The car would have done 35-40 MPH without issue, but I needed to make it home from Beaverton too; so efficient choices were the play of the day. Took Skyline down to Canyon, and cruised nice and easy out to the meeting on the other side of 217. No problems, static cell voltage after the meeting ranged from 2.2-2.35V; ~60% SOC (state of charge). Not looking too great for an uninterrupted drive home, with 18 miles to go!

So, I planned my trip to go back up Canyon, then I would hop on Hwy26 at Sylvan and regen all the way down. At that point I could drop off at the Jefferson exit and take side streets, or detour into work or another charge spot if needed. Started climbing Canyon, and about 1.5 miles from the Sylvan entrance to Hwy26 the old girl started petering out. The one battery I was monitoring with my DMM (digital multi-meter) was actually going up in voltage; telling me there was another battery somewhere that was dying and going high resistance, inhibiting the rest of the pack. So I slowed down to 20 MPH again and stayed to the right, again fortunately no traffic. Go to where Canyon splits off to either Hwy26 westbound or Sylvan and I had the pedal to the floor, doing about 15 MPH. Longest Sylvan hill climb ever! At least for me.

Made it over the crest doing no more than 5 MPH, and started the glorious descent down Hwy 26 with regen active whenever I could. Pulled into work and plugged in, expecting about 2,000 watts of charging on 208V. Since I was waiting, I located the lowest battery and manually charged that one with an additional 12V charger to offset the deficiency it had picked up. Checked my overall pack current...2.1A charging current. Meaning I was only charging at about 400 watts...not good! Didn't have the laptop with the charger connection software on it, so after doing basic troubleshooting I just resigned myself to spending some time there waiting for a charge. Ended up falling asleep in the driver's seat for a few hours, woke up around 4 AM and finished the drive home. All in a day's work, right?

Moral of the story: EVs have come a long way since the 1990s! But sometimes it is just fun to play with the older vehicles, even if they don't always play nice back. Makes you appreciate how much more refined, capable and reliable they are nowadays.

Tony Foley