It’s All About the Electrons

As the song goes, “…You don’t know what you’ve got ’till it’s gone…”
While the Four Wheel Camper’s batteries and functionality depend on the sun, so does the Evelo Aurora e-bike’s battery – once I’m out on tour. It siphons power off the Four Wheel’s house pack to keep itself charged. All good things come to an end, and the original Evelo 48V 10Ah battery that shipped with the bike has now cycled enough times that it is no longer very useful for anything but the shortest, easiest errands. It actually began to sag a year ago, so this is a belated replacement. The spare battery that I ordered with the bike immediately showed signs of swelling and proved defective, so Evelo replaced it. That replacement broke an internal wire right after its warranty had expired, right at a place that was not possible for me to repair.
Evelo sells its replacements at $700 per – almost three times the market cost of this battery voltage and capacity. They are nice batteries, since they come with a marginal-quality spring carrier rack on top of the case, and they are well-protected against weather except when their spring-loaded charging port covers refuse to stay closed. The Aurora’s frame carries its battery case in a steel tube perimeter hoop, which gives it some protection in a crash and allows it to be key-locked in place, a useful trait in urban environments. It’s a well-integrated system that allows the battery case to be buried halfway down into the hoop, which allows a seatpost carrier to be installed above it if need be. But an average of $233/year for e-bike batteries, especially at this minimal capacity level, is simply not acceptable to me. Time for a change. Many e-cyclists would toss the whole thing and start over with a vintage bike and a gas engine drive kit, which is much cheaper and faster on the level. They don’t do so well at inching up steep, rough trails and I’m not yet ready to start packing cans of gasoline. But it’s a choice.

The Evelo battery with a seatpost-mount carrier above it, which is used to hold a basket.
Since I’m not really conversant in e-bike geekdom, all I knew was that how the battery cells were wired up together was referred to Read more…