makro

I'm trying to phase out my car, so I want to be able to have something like a 120 mile range on my Ebike - definitely a lot, I know.

Using the motor from the E-Bikekit, and lead-acid batteries (for cheapness), I'm not exactly sure what to do.

I could probably get a range upwards of 200 miles using a 48V system using Trojan golf cart batteries, but the problem is that the lightest 12V ones are about 50 pounds. 200 pounds - even a 36V system at 150 is pretty heavy.

Right now I'm trying to puzzle out a system to mount them on a $200 mountain bike from Target. I know electronics fairly well, but I wouldn't be able to weld or make a sidecar or something to save my life.

Does anyone have any suggestions on either how to mount them, or a different type of battery (that isn't stupidly expensive like Li-Ion) to use to get 120mi+ range?

Thanks

Edit: Would overamping a controller damage it, or would it just take as many amps as it could handle? This is probably more important than the other question.

rscamp

Are you going to pedal? How much? Hills?

You need to predict your energy consumption per unit of distance before you can size the battery. Heavy batteries will work against you. Practically, to maximize range you need the highest mass energy density batteries, slower speeds, low rolling resistance tires with the correct pressure, human assist, fairing (if practical) and an appropriate supply voltage/motor combination for maximum efficiency at the desired speed.

dgk02

SLA batteries are not the way to go. Initially cheaper yes, but if you're planning on doing it for a long time then you need to consider recharging cycles and SLA falls down there. You also can't drain them as far without killing them. At least, that's what I understand from being around here for a bit.

nwmtnbkr

I agree that SLAs aren't the way to go. I lived with my OEM 24V 10AH SLA battery alone until this spring (I installed the Currie conversion kit last July). This spring, I built a 24V 20AH LIFEPO4 pack using Thundersky cells that I bought from an American distributor (Elite Power Solutions in Arizona). The increased power in the LIFEPO4 battery pack is impressive. I still have my SLA pack , but it's loosing capacity and I'll be building a second LIFEPO4 pack this summer. With my new LIFEPO4 pack and the SLA pack mounted in the Currie rear rack, I believe I'll have no problems traveling to a town that's farther from me--it will be a 40-mile round trip. However, I alway pedal. Once I have 2 LIFEPO4 packs, I believe I'll have no problems with 50-60 miles, again, always pedaling. At present, I've taken a lot of 20 mile trips using the LIFEPO4 pack only and still have had lots of power in my pack, and I'm in a very mountainous area (west of Glacier National Park). I was able to buy the Thundersky cells on sale and my total cost for 8 cells was $208 plus shipping, which was $15 for me. Their regular price isn't too bad--8 cells run $240. If you take care of them, LIFEPO4 are supposed to have 2000 charging cycles compared to SLAs 600, a cost savings in the end.

morph999 

120 mile range on an e-bike? Maybe on a trike with a 36v40AH lifepo4 battery is possible. Or maybe if you get a 48v20AH lifepo4 and use some kind 10 amp controller that conserves energy better and also maybe use regen with it you could get some kind of range like that. Most controllers are 20 amp. Maybe you could get a 20 amp controller and get a cycle analyst from ebikes.ca and then limit the current supply to only 10 amps and then it would be more like a bionx bike and just supply a little extra power but if you are going 100 miles and pedaling, you'll still sweat your balls off so I don't see the point. If you want 100 mile range, I'd just spend the $2000 on a really nice lightweight racing bike. You could get 45 - 50 mile range on an e-bike but not much more than that without some really big lifepo4 batteries. And definitely not possible with SLA (lead acid) batteries.

morph999 

Actually, if you really want to get 120 mile range, it would probably be possible if you put a 48v20AH lifepo4 back in the back and 48v20AH lifepo4 pack in a front rack and then you get 3 miles per AH by using a nine continent motor and a 20 amp controller then you could probably get a 100 - 120 mile range without pedaling. Or maybe you could use LIPO and build a 48v40AH lipo pack and do it but that might be kind of dangerous since LIPO gets hot. You'll probably need 48v40AH of lithium at least to get 100 - 120 mile range. If you can get that on a bike, it's doable otherwise, you'll have to pedal 50 % of the time to get that kind of range with a smaller lifepo4 pack. Also, if you want to get maximum range, do some research on the most efficient hub motor I think nine-continent is pretty efficient but my not be the most efficient. The most efficient might be a heinzemann or bafang or soemthing like that.

dgk02

But it's not going to be done cheaply.

15rms

Makro maybe you could consider using an internal combustion engine. I have a recumbent with a Subaru 1.6 hp engine on it. It gets 34 miles on its 21 ounce tank. That is running at a very high speed and I have stuffed steel wool in the muffler to make it quiet. You could easily and cheaply build a bike that would get 120 miles with very little gas. Possibly a half gallon. It can't be used everywhere however can be used to get great distance on the side of a road. To me that makes more sense than trying to use heavy batteries to go the distance.