djbills
1 µW
Hi All - I picked up a Rad2Go/Qelectric Expresso S ebike/scooter with a dead pack for free that I've been wanting to get back on the road, and I think I'm going to get on it this summer. Will take the chance to make some improvements while I'm in there. 
Here are the original specs -
http://www.sadoun.com/Motorcycles/Scooters/Qelectric/Expresso-S-Electric-scooter.htm
Definitely looking for recommendations - I'll vomit out some ideas but I'd love to know what you all more experienced folks would do in the same situation!
My commute is 10-11 miles, and I'd like to try to hack the top speed up into more of the 30-35mph range, probably as fast as I'd want to go on something so light. Might have to improve the brakes a bit.
Batteries - as you can see, stock pack was 48v 14ah SLA, weight ~38lbs. I've been meaning to toss in some old UPS batteries temporarily just to run it around the neighborhood and verify it feels like something I want to drop the time on. I think it'll be fine? Not sure, I suppose up from here is a "real" electric scooter but those have to be licensed and things like that - no thanks. This seems like the buy in level I want to be at. Another toy.
Anyway - I'm going back and forth on it and I think I want to go low budget, but still try to get something decent if possible. I know I could drop $600 some on a Ping pack and be done with it, but I don't have a lot of disposable income right now - would love to do it for less.
Current (pun intended) research is pointing me towards a batch of Headway cylindrical 10ah cells that a friend is unloading, scrapping from an ATV project he's changing up. I could get 1 string of 48v (15) for pretty cheap... $150. or I could double up with a 2nd string in parallel - and still only 21lbs total. Not totally sure on range guesses - what do you all think? With 1 string @ 10ah, even with the reduced weight, I think I'd be lucky to get 8 miles. I think the range would be reliably around 15 or so miles with the dual strings and that'll get me where I need to be, and storage shouldn't be a problem, although I would probably have to split the pack between floorboard and "toilet bowl" sized area under the seat. No worries.
Another option - there's also a cheap batch of Vectrix salvaged Nimh batteries for sale in the area - a bit more bulk but they are cheeeeap. I'm not sure about Nimh, though - 1.2v so would need 40 and they are a bit larger. BMS with nimh? Charger? BMS? I think I'd rather use a chemistry I feel better about, so tossed this aside.
I had a friend build a nice little short range bike with a Ryobi mower battery - I think they clock in at 40v and are 5ah. So I'd probably have to parallel 2 or 3 (and probably knock down to a 36v controller to avoid undervolting cutoff? unsure of c rating). But what I like about this idea is I might be able to also pop them out and use them in another Currie ebike I have in place of the SLA batteries there. That might be awesome, since it's more of an e-assist bike and sees a good amount of use (but I hate the rear end weight of 2 SLA's). Thinking about this and wondering how far these might get me, and how terrible an idea it'd be to try to source these used... and just pray they are somewhat equal capacity between them.
other bits -
Motor - stock is 500w brushless. I'd probably just leave that in there and run it harder - might be fine. If it lets some smoke out, I imagine it wouldn't be difficult to swap in a 1000w model.
Controller - stock unknown, assumed 48v, 20A. I think a 30A would be an easy swap - question is, would that get me up into the top speed I'm looking for? 40A might be a better bet, but that would be running quite a bit of current through that little 500w motor. Hmmm...
BMS - seems no shortage of cheap BMS's out there. Probably some $50 one would be fine. Any recs? Not too concerned as long as it's reliable. Ryobi batteries seem to have a bms on the unit, which is mildly interesting.
Charger: I'll probably pick up a no frills 5A charger. or a bunch of ryobi chargers, which actually doesn't seem half bad (I'm warming up to this idea).
Anyway - any tips appreciated. I'll attach some random pics of the bike.
Here are the original specs -
http://www.sadoun.com/Motorcycles/Scooters/Qelectric/Expresso-S-Electric-scooter.htm
Definitely looking for recommendations - I'll vomit out some ideas but I'd love to know what you all more experienced folks would do in the same situation!
My commute is 10-11 miles, and I'd like to try to hack the top speed up into more of the 30-35mph range, probably as fast as I'd want to go on something so light. Might have to improve the brakes a bit.
Batteries - as you can see, stock pack was 48v 14ah SLA, weight ~38lbs. I've been meaning to toss in some old UPS batteries temporarily just to run it around the neighborhood and verify it feels like something I want to drop the time on. I think it'll be fine? Not sure, I suppose up from here is a "real" electric scooter but those have to be licensed and things like that - no thanks. This seems like the buy in level I want to be at. Another toy.
Anyway - I'm going back and forth on it and I think I want to go low budget, but still try to get something decent if possible. I know I could drop $600 some on a Ping pack and be done with it, but I don't have a lot of disposable income right now - would love to do it for less.
Current (pun intended) research is pointing me towards a batch of Headway cylindrical 10ah cells that a friend is unloading, scrapping from an ATV project he's changing up. I could get 1 string of 48v (15) for pretty cheap... $150. or I could double up with a 2nd string in parallel - and still only 21lbs total. Not totally sure on range guesses - what do you all think? With 1 string @ 10ah, even with the reduced weight, I think I'd be lucky to get 8 miles. I think the range would be reliably around 15 or so miles with the dual strings and that'll get me where I need to be, and storage shouldn't be a problem, although I would probably have to split the pack between floorboard and "toilet bowl" sized area under the seat. No worries.
Another option - there's also a cheap batch of Vectrix salvaged Nimh batteries for sale in the area - a bit more bulk but they are cheeeeap. I'm not sure about Nimh, though - 1.2v so would need 40 and they are a bit larger. BMS with nimh? Charger? BMS? I think I'd rather use a chemistry I feel better about, so tossed this aside.
I had a friend build a nice little short range bike with a Ryobi mower battery - I think they clock in at 40v and are 5ah. So I'd probably have to parallel 2 or 3 (and probably knock down to a 36v controller to avoid undervolting cutoff? unsure of c rating). But what I like about this idea is I might be able to also pop them out and use them in another Currie ebike I have in place of the SLA batteries there. That might be awesome, since it's more of an e-assist bike and sees a good amount of use (but I hate the rear end weight of 2 SLA's). Thinking about this and wondering how far these might get me, and how terrible an idea it'd be to try to source these used... and just pray they are somewhat equal capacity between them.
other bits -
Motor - stock is 500w brushless. I'd probably just leave that in there and run it harder - might be fine. If it lets some smoke out, I imagine it wouldn't be difficult to swap in a 1000w model.
Controller - stock unknown, assumed 48v, 20A. I think a 30A would be an easy swap - question is, would that get me up into the top speed I'm looking for? 40A might be a better bet, but that would be running quite a bit of current through that little 500w motor. Hmmm...
BMS - seems no shortage of cheap BMS's out there. Probably some $50 one would be fine. Any recs? Not too concerned as long as it's reliable. Ryobi batteries seem to have a bms on the unit, which is mildly interesting.
Charger: I'll probably pick up a no frills 5A charger. or a bunch of ryobi chargers, which actually doesn't seem half bad (I'm warming up to this idea).
Anyway - any tips appreciated. I'll attach some random pics of the bike.
