ElectricBikeSquatch
100 µW
So, let's say you want to squeeze all the juice out of a quick public EV charger visit to make a light vehicle work for long-distance travel. Maybe you can charge your battery at 2C or more and be within specs by a very safe margin?
Just for the sake of discussion, let's make up a touring ebike battery, a motorcycle battery, and a battery in some kind of street-legal light car. The ebike has 14s8p 21700s and will accept 58.8V at 60A, the motorcycle has a 20s16p pack that can charge at 84V at 120A, and the home-made car has a 60S 2P LTO pack that can hypothetically take 120A at 168V. That's 3.5, 10, and 20kw respectively. As far as I know, even crappy level 2 chargers will give you 3500w, maybe less so for 10 or 20 kilowatts, but don't a lot of them, in fact, do roughly that much?
Those are the greedy mouths we could potentially feed. We'll also assume, for longevity, we're only ever charging them to a maximum of ~80 or 85% at such a high rate, with active temperature monitoring, and high-quality BMSs in these hypothetical packs.
Ok, so...how do you get anywhere close to any of those with something portable that can effectively plug into and accept AC current from a public charger, in each case?
I've seen some questionable quality 'waterproof e-scooter chargers' that might do half of what the touring ebike 21700 pack can handle, and they're like $500.
I've seen all sorts of $300ish options that will...barely do a third of that.
I'm also aware of the concept of rectified mains, which is why our pretend car's pack charges at 168V (it also has an EM57 motor, let's say, so we want those 2500 RPMs).
Is there a practical route to CC/CV control of a source like that which would be safe for battery charging at that amperage and such a high voltage? Are they....less expensive than the $500 30-amp AC chargers I'm balking at?
Curious if anyone else has been thinking about this.
Just for the sake of discussion, let's make up a touring ebike battery, a motorcycle battery, and a battery in some kind of street-legal light car. The ebike has 14s8p 21700s and will accept 58.8V at 60A, the motorcycle has a 20s16p pack that can charge at 84V at 120A, and the home-made car has a 60S 2P LTO pack that can hypothetically take 120A at 168V. That's 3.5, 10, and 20kw respectively. As far as I know, even crappy level 2 chargers will give you 3500w, maybe less so for 10 or 20 kilowatts, but don't a lot of them, in fact, do roughly that much?
Those are the greedy mouths we could potentially feed. We'll also assume, for longevity, we're only ever charging them to a maximum of ~80 or 85% at such a high rate, with active temperature monitoring, and high-quality BMSs in these hypothetical packs.
Ok, so...how do you get anywhere close to any of those with something portable that can effectively plug into and accept AC current from a public charger, in each case?
I've seen some questionable quality 'waterproof e-scooter chargers' that might do half of what the touring ebike 21700 pack can handle, and they're like $500.
I've seen all sorts of $300ish options that will...barely do a third of that.
I'm also aware of the concept of rectified mains, which is why our pretend car's pack charges at 168V (it also has an EM57 motor, let's say, so we want those 2500 RPMs).
Is there a practical route to CC/CV control of a source like that which would be safe for battery charging at that amperage and such a high voltage? Are they....less expensive than the $500 30-amp AC chargers I'm balking at?
Curious if anyone else has been thinking about this.
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