asmodaeus

Hello,

I recently purchased a 48v/1000watt brushless hub motor from Golden Motors. However, I'm not sure which voltage of battery I need to run it. It would stand to reason that I'd need a 48v one in my mind, as the motor is 48v, but I may be wrong as I've never built anything like this before. Can someone set me straight and possibly reccomend the best kind of battery to do the job? Thanks,

Mike

topeka111

Did you read the sticky on batteries?

ShinyBiker

You're probably looking at 4 12V Sealed Lead Acid (SLAs) batts if you are on a budget. There are other lighter technologies, but they will be more expensive. People always rave about Ping on ebay and he sells Lipos for cheap on ebay. If you want peace of mind, you can always go to ebikes.ca.

asmodaeus

I did read the sticky for batteries, but is that the correct voltage I need?

asmodaeus

So, what kind of AH am I looking for for a 1000watt motor? I see all kinds of 48v batteries, but I'm not sure which one I need still.

cerewa

48V is what you need.

a 48v battery "puts out 48 volts" (in reality it normally puts out somewhere between 40 and 54 volts depending on battery type and circumstances). voltage is kind of like air pressure or water pressure in a tube, except that it's "electron pressure" in a wire. It does not measure "power", just "pressure".

if you bought a 48 volt kit from Goldenmotor, what you actually got was a controller designed for a 48 volt battery, and a motor that works well with that controller. (the motor will work fine at 72v or 24v with a controller that is made for the appropriate voltage.)

your 1000w motor&controller work best with a 48v battery that can put out at least 20 amps. (amps, not amp hours)

lead-acid batteries are popular for their cheap start-up cost... and lithium iron phosphate batteries are popular for their light weight and long service life (and therefore, they are sometimes cheaper in the long run than lead acid).

How many amp HOURS do you need? here is a rough guess: at 48 volts (no pedaling) you will need about 0.5 amp hours per mile of range if your batteries are LiFePO4. If you use lead acid batteries, you will need about 1 amp hour per mile of range. If you travel by 50% pedal-power 50% motor-power your range will double.

If you use inexpensive e-bay LiFePO4 batteries, you will need at least 10 amp hours for your system to work well at all; you will need 15 or maybe 20 amp hours for your system to give its best high-power performance. (keeping in mind, for a 1000 watt motor, peak-performance is really quite impressive.)

asmodaeus

OK, so here's my plan: I could do a chain of 4 12v 20ah SLA batteries as described here https://www.batteryspace.com/index.as...OD&ProdID=2177 (which would weigh 60 lbs, eek, but it's an e-trike, really, so I can stick all that weight in the back basket)

Do those batteries look good. Also, do I need to charge them seperately, or can I get 1 48v charger and charge the chain?

Thanks for your help.

karma

you can charge them together, i have used those cells on the back rack there way to heavy. you wana keep
them as low as possible like in the frame around the front down tube. trust me go with a cheap lifepo4 pack.

BroadwayJoe

I wouldn't deal with more than 7-8AH SLA. Anything more and it's just too dang heavy. If you need 20AH do as Karma suggests - cheap lifepo4.