Yesterday I finally got a chance to do a "proper" bike trip on my e-bike. And I finally got to establish a good, new baseline for my battery pack.
Name: causeway trip
Trip time: 02:05:50
TripDistance: 34.1 mi
Average speed: 16.3 mi/h
Maximum speed: 35 mi/h
Climbed altitude: 1432 ft
The trip started out with a familiar jaunt through the network of South Burlington rec. trails. From there I rode up to the UVM campus, out to Main St. and hit downtown. For fun and people watching, I walked my bike up Church St. Although I probably looked a little odd (perhaps like a Burlington bike cop) I am constantly amazed at the ability to bring something like an e-bike right into the middle of a pedestrian mall, walk through it, hop on on the other side, and continue on. Try to do that with a car, motorcycle, scooter or even a moped!
Rode down to the waterfront to get a quick look at the water level. Definitely getting up there. Breakwaters (restaurant/bar) is flooded, and there are extra ramps around the boat loading areas at the boathouse. I remembered that they had done a big overhaul on the Colchester Causeway (which had been beaten to a pulp during Irene after being brutalized by flooding of spring 2011). I decided I wanted to get a look at it before it was wrecked again (ha). I took the bike path up. It was kind of fun, but a little annoying as I felt like I was in a bit of a hurry. I am always very respectful of pedestrians and regular ped-power bikes (don't want to ruin it for everybody) so there was a lot of braking and excusing.
The work they did on the causeway is phenomenal. Not only is it perfectly smooth and flat (not a single pothole along the whole thing), but they also managed to widen it quite a bit. No more almost wiping out oncoming traffic or when passing people. There were many places where I was able to hold it almost wide open (25-30 mph) for great distances. Of course as soon as I saw anyone I would slow it way down. The last thing we need is someone getting hurt or even nervous, as that will be the end of "the Wild West" for e-bikes around here. I'm sure it's only a matter of time anyway (as e-bike prices come down, more idiots will own them).
I was keeping an eye on my battery pack min. voltage (essentially estimating when the battery would die by observing how much voltage sag vs. throttle/load there was). The pack seemed very strong all the way there. After I rode as far as I dared (which might have been a little too far), I turned around and started the long haul back to Shelburne. I was easily 14-15 miles away. This time I took main roads all the way home. North Avenue was a real treat as there was very little traffic, and I was able to roll full speed (while being as gentle as I could on the battery), and not have to stop for traffic lights or turning cars. In about 20 minutes, I had made it all the way back to Shelburne Rd, when, without any warning, the pack cut out. Just "plink" (no sound effect), no power, followed by the foreboding thought of having to pedal 80 lbs of bike 4 miles home. It really wasn't so bad though. I needed the work out anyway (whoever thought that owning an electric bike meant you get no exercise is sorely mistaken). I got home in about 20 minutes, taking it slow.
So in retrospect, the battery almost certainly cutout due to cell (#1) under voltage. The pack voltage minimum was 46 volts, which is fairly high, so it's doubtful that the entire pack was dead when cut out happened. Of course I should have expected this, as #1 is the damaged cell. In all, I am pretty content knowing my battery pack can still take me 34+ miles after all it's been through.