Battery Vehicle Society

After nearly a week off the road where I replaced some of my lithium and tidied up my wiring loom for the BMS my car is now officially back on the road. After a slight problem on Wednesday resulting in the death of a spare cell I'd had in the garage for a year, I've repackaged things (again) and all is well.

This morning I took it for a quick 6 mile sprint, giving it lots of stop/start driving and drain from the heater etc. The batteries weren't fully balanced so this short trip let the new cells settle down next to the good old ones.

Then, about an hour ago I got back from a nice 17 mile jaunt, which got the batteries nice and toasty ( 40 degrees C if anyone's interested). There seems to be very little voltage drop between the cells, so I think they're getting nicely balanced. As some of the cells are old they've got a higher internal resistance so they'll probably drift apart slightly with charging from the new ones.

However, the El is back on the road again and ready for my new clients next month. I'm hoping that the El can quite happily handle the 30 mile round trips I'm wanting it to do without slowing to a crawl on the big hills we have round here. Initial results are nice and healthy, with the largest hill I pointed it at today (about a 1 in 13) being scaled at 30 mph and drawing the maximum 125A as set by the car's limiter. If tomorrow's test drive (I'm shooting for a 40 mile trip with Kate behind with a Generator in case anything goes wrong like it did on Wednesday) goes well I'll tweak the BMS to allow 200A through the controller. 200A would shorten range significantly but enable me to really hold my own on hills in Bristol.

Stay Tuned!

Really pleased to hear that you are on the road again

Mary.

These little "el" cars are a real love/hate relationship - mine is down to a range of 8km

Should improve once I get some new batteries.....


Glad you're back up and running

Wooooh you been playing batteries again Nikki I thought you'd gone a bit quiet. Good luck with the run tomorrow!

Batteries seem to be a big issue and there's been a few jazzy ones gone pear shaped lately what with Peter's Solar van too.

So, back on the road and after one week we have the following to report:

On Saturday and Sunday last week I did two long trips. Saturday totalled 25 miles and Sunday a 35 miles.

Then on Monday I had a bit of a slow day in the car (only 15 miles) followed by a whopping 36 on Tuesday. That included a 16% hill over 3/4 of a mile long!

Wednesday was a slow day for the car with only a total of 6 miles being covered.

Thursday I did 40 in total, split between a morning drive and then an evening 25 mile round trip to a concert I was playing in.

Friday we managed about 29 miles, including climbing the side of Clifton Gorge on the steep road there. Top speed while climbing an impressive 23mph. (This hill must be about 18%)

Total mileage for this week then is pushing 190 miles. It's the most I've ever done in one week in the car and I'm very impressed. I think from the battery status at the end of my longer trips that I could in fact do about 50 miles on a charge if I was careful. My cruising speed on flat country roads is now about 40 mph.

On Wednesday I had a little play with the car's power circuits and set the maximum current to 200A instead of the 120A as set by the car's circuitry at the factory. 0-30 time from a fully charged pack went from the standard 8-9 seconds to 6.5! I even got pushed into the back of the seat. I have it on good authority that the car will cope with 200 A without breaking the belt or damaging anything so I'm going to probably have a play with that in the coming weeks. Eventually I want a switch so I can choose between range and acceleration. Obviously, on the days I work in Bristol it'd be nice to have really hot acceleration for the town work - but on the days when I work out of town I'd like to be sure that the range I have would be sufficient.

Anyway - that's my report thus far

Nikki.

Nice one Nikki,

Glad its all OK. If you do want to upgrade the controller have a look at the curtis 1207 range. They have a really nice feature called multi-mode. Basically you programme the controller up for two totally different driving modes which can be switch even whilst being driven. Same system that is fitted to the G-wiz
regards
Dave

HI Dave,

Well, thanks for that. I've currently got the 48V version of the 1204x in it. That will supply the 200A I need and after fitting the right fuse this afternoon all seems to be okay

I've got a plan up my sleeve for a slightly easier and cheaper way to change set-up involving a PDA

Nikki.