Electric Bikes - best way to extend range?

My new e-bike came with a 10ah 48v LiFePo4. This cell barely gets me to work & home & I'd like a bit more.
The battery & 40a controller fit into a beam rack mounted soft bag.
http://www.outsideoutfitters.com/p-537-topeak-mtx-trunk-bag-ex.aspx
This looks nice, but it leaves me with little space to work with & it gets screaming hot very quickly.

I'm thinking of mounting the controller on the bottom of the beam rack which would keep it a lot cooler & give me a good bit more space for a 2nd LiFePo4 48v 10ah that I can connect in parallel to double my range.

Does this sound like a good idea, or should I just see if I can get the most AH battery I can that will fit into the bag?
I'd really like to get a 60v 30AH but not sure if I have the room for it so I may just look into a 48v 20 or 30AH & probably going to order it from Ping.

Can you clarify you range? are you doing the round trip on 1 charge, or are you recharging at work?

If you are doing the round trip on a single charge, I'd suggest a second charger or carry your charger with you.

It takes me about 8 minutes to get to my place of employment if I'm liberal with the throttle & a bit more if I go conservative & I can make it both ways on a single charge but just barely. I sometimes make a stop off or 2 & this nearly always leaves me pedaling this extremely heavy bike up hills for the last few blocks. I'd say its about 3 miles 1 way if I use the direct route.

Perhaps a 2nd charger would be the best way to go, but my employer is a bit stingy about the electric bill, sometimes going around unplugging anything that he sees as "unnecessary" & quite often things that are very necessary such as battery chargers for the tools I use on a daily basis which now include my bike.

My real goal is to get my range high enough that I can go nearly anyplace I want locally without worry of a dead battery on the trip home. If I could get up to about 30 miles as I thought I would when I bought this bike, I'd be extremely pleased. However I don't think thats going to happen now that I understand a bit more about the way they work.

Figure out how much electricity your charger uses to fill an empty battery, calculate in function of electricity cost, then offer your employer grossly more then that. EG 10A*48V = 480wh, with a pretty conservative 90% eff that's 533wh, so at 8 pennies per kwh that's a bit over 4 pennies, so show the math and offer say a quarter per day to be allowed to plug in at work. If he's that cheap, then he'll accept willingly and your effective range will go up a lot.

My ebike has once gone 50 kms in a day using 0 w/km tho the battery was full, altho obviously a regular bike would have been faster and less tireing in that case. Still if you use assist only starting from stops and helping uphill, you can ride quite a lot further and faster then you normally could on a regular bike. But just learn to accept to accelerate slower, go slower, and lean less heavely on the battery, then your ebike's range won't be limited by battery capacity, it'll be limited by how long you want to spend on a bike.

I use the same Topeak bag for my 24V 20AH duct tape pack, it fits with little room to spare.

I would highly recommend removing the controller from the bag if for no other reason than cooling.

Once you get that done you'll know how much space is left in the bag for more or bigger batteries.

If you go the multiple battery route you may want to consider a front bag for the second battery just to balance the weight. My pack weighs about 15 lbs which doesn't sound like much until it's out of juice and I have to pedal it around.

a 48v10Ah holds 0.48 kilowatt-hours (480 watt-hours) of energy.

If I'm not mistaken, this represents something like 750 watt hours (0.75kWh) of energy input to the charger to get the 480 watt hours out of the battery.

What this means is that in the USA each full charge (from 100% dis-charged) for that battery costs somewhere on the order of 7 cents to 20 cents.

Too much controller, too little pedaling, and too little battery. Going to a 20a controller should help until you get more battery.

There's something wrong with your battery. A 7-mile round trip should only use 4ah or so.

The ping 48 20 ah battery will go 45 miles easily.

I've gone over 35 miles COUNTLESS times with my 36v/15ah battery... but you have a 48v... and most probably pressing full throttle gets you out of your pedaling range (beyond 20mph)... but when I'm full throttle with my 36v battery, I'm pedaling at the top end of my gearing at maybe 16-18mph, it's better mated for human pedal power to increase efficiency of the entire system.

my boss once complained about the cost of coffee, when I pulled a $20 bill out of my pocket he refused to take it.

There's something wrong with your battery. A 7-mile round trip should only use 4ah or so.

The ping 48 20 ah battery will go 45 miles easily.

I thought the same at 1st as well, but if you think about it & do the math , it's the controller thats kiling the battery so quickly. Correct me if I'm wrong , but since my controller is a strong 40 amps, I would need a 40ah pack to get 1 hr of throttle usage. My pack is 1/4 of that at 10ah so I get about 15mins of total throttle use.

Keep in mind that I'm 6'3" & 260 lbs on a bike that weighs in around 60 lbs with all the accouterments.

The ping 48 20 ah battery will go 45 miles easily.

Depends on a lot of factors. I used to get 40 miles regularly with a battery that's 1/4 that size, but only by pedaling a lot, and I only weigh 130 pounds, and I didn't go any faster than 18mph.

If you have enough restraint, you can save a lot of battery just by going light on the throttle from a stand-still, and limiting yourself to going less than your top speed, but that might not be what you want.

With the heaviest, most wasteful way of using the throttle on my bike, I can burn up 24 Ahr of Battery with a 26km trip.

Based on recharge time, the same trip typically uses about 15-16Ahr, and thats is without any conscious efforts to conserve battery power.

At times, I've stretched out a 12Ahr battery, because I discovered that one of my battery packs was not charged.

I hope this helps.

Why don't you invest in a watts up meter for $50 to find out what the true capacity of your battery is and how much you are burning up per mile? It's good to have one regardless.

Why don't you invest in a watts up meter for $50 to find out what the true capacity of your battery is and how much you are burning up per mile? It's good to have one regardless.

I was planning on getting another multimeter in the near future. I've had a cheap one in the past but haven't seen it in a few years so I suppose I misplaced it during my last move or 2.

I don't mind getting a decent 1, so are there any suggestions you can offer as to what to look for in brand , model, and/or features?

Try something like this. It's not really a DMM.
http://www.powerwerx.com/product.asp?ProdID=3809

Cheaper on ebay as well. You keep it on the handlebars and measure amp-hours used as well as instant amps, watts.

I was actually thinking of getting a cycle analyst. I have a crystalyte controller with the pigtail ready & waiting for one.

I still want to get a decent multimeter. I may decide to endeavor into battery building myself & this would be an essential tool.

Good choice. Then you can limit down your amps too.

I don't want to beat a dead horse, a lot of what folks are saying here rings true, especially about how to extend your range by making smart use of the throttle.

i have a 12ah 48volt lifepo4 , 20a controller with 408 motor. Making smart use of the throttle i get 60km out of a full charge. That about 5km per ah. If i use it liberally i get around 3km/ah.

i also got the cycle analyst, it's super great and yes you can set it to control maximum amps drawn and cut off voltage as well as top speed... only thing is, you need to make sure you waterproof the thing, otherwise if you're like me, riding when it pours, your analyst will fry, which happened to me, but the good folks at ebikes.ca were kind enough to fix it under warranty.

anywho .. what i'm really after is the type of motor you have. is it a 400 or a 500 series?

with regards to the controller, i place it right behind and under my chair , so it gets lots of cool air when riding. i fasten it using plumbing restraints .. it's an alloy belt with a screw that you turn to tighten the belt. i don't know the exact name but you can get it at any home depot type store in their plumbing or air vent sections. i use two belts to fasten the controller to the bike, i then ductape the whole thing so to make it nice an uniform. trust me, if anyone wants your controller, they will realise quickly its solidly attached to your bike, plus they need to know what to do with it. so i won't worry too much about it getting stolen. the controler really belongs on the bike and in open space, just make sure it's water proofed. you're gonna laugh, mine is wrapped in plastic and duct tape, and it doesn't get hot at all.. maybe because it's a 20a vs a 40a.. but i also think it being outside must be helping a great deal.

i'm not a pro.. just a jo :-)) :innocent:

i've attached a pic of my bike and where the controller is.. oh and also, i keep my battery in the front not the back, less weight on the back wheel etc.. bike is more balanced that way.. ok ciao for now!:D

The motor I have is a BMC geared brushless high speed rear hub.
The controller is a crystalyte digital 40a 36-72volt.
The bike runs fantastically. I estimate a bit over 30mph top speed on level ground & has nice torque also.
I just expected a bit more range when I ordered it but now that I've learned a bit more about E-bikes it is just what is expected with that setup.
I think I ma leaning towards a 2nd 48v 10 ah & run it in parallel with my existing pack.

Thats probly a good choice. I'm running a 36V 18Ah battery and get 40+ KM on a charge if I don't go over the massive hill. That sucks 10Km off the range because I am very out of shape and its a 15% grade. I was actually putting on about 2lbs of leg muscle every time I went over that hill even with the electric assist.

Either that or I gained more weight. :(

ok.. thanks. I'm not familiar with BMC motor, so i can't really compare it to my experience. but i agree with you that in your case it may very well be your controller, allowing amps to be drawn and leading you to shorter range... a cycle analyst would be a fine solution without having to change controller, is my opinion and i can back this up because i have such an analyst..

when you limit your amps, you'll notice less torque; i'm sure you can find a happy medium and extend your range this way

I forgot to state that the motor is 600w.They also make an older model that is 400w. I looked at many alternatives before I ordered it & nearly everyone that has bought one loved it. There were a few exceptions where they say the motor was junk but I think that those are just those people who are never pleased no matter what or the motor was mishandled.
I highly recommend BMC brushless motors based on my experience so far. It is extremely fast & has marvelous torque. With my considerable weight on it , it still reaches a solid 30 mph in under 4 seconds on level ground.

what's the noise level of the motor? do you sound like a moped when you scoot down the road? I wanted to get a geared mortor, but the purported noise was of concern to me.

It runs very quietly. I'd say it is a tiny bit louder than a quality household fan & much quieter than an electric golf cart.

It runs very quietly. I'd say it is a tiny bit louder than a quality household fan & much quieter than an electric golf cart.

That's sweet.

Regarding the Cycle Analyst, I disabled all limitations and the trip that normally takes 3 ah now takes 8 ah. I suspect that if you were to plug your controller to the cycle analyst you can limit max amperage drawn and get a lot more range from your bike.

I think most of the loss happens when you start off from rest; if you're only limiting the amperage drawn to say 25amps, you'll waste less.

anywho.. I hope you find this experiment useful.:thumb:

a 48v 20ah setup 345x140x140 would be best use a 70 kg carrier (Axiom makes a good product). Add a tire with smooth bottom - can have stubby sides for slipping (Canadian Tire special) - 80 lbs. pressure. Best front drive for gravel trail corners. Most hubs work most efficiently at around 80 to 90 percent throttle. My experience is 20 to 22 mph for a 30 mph (32 tops) hub. Use the pedals to get a feeling of well being - this can add at least 10 miles to a 50 mile trip - Should be able to get 60 miles easily on a packed gravel surface - 70 on pavement - weight is a factor - I weigh 180 lb - half the weight would increase by 25 percent. Call your relatives before you test the long haul out - they WILL have to pick you up as the battery dies instantly. What's with controller mounting and rain - get some recycle bags - black from Canadian Tire - they look sharp and cover the battery and controller.

Your trouble is you are going to fast. That 48volt LiFePo4 battery has very low internal resistance with negative temperature coeffcient. Meaning the hotter it gets the more current you can draw from it. And at 30 MPH that's a heck of a lot of power. Your using all the 600 watts of that motor, that's like 12.5 amp. And you only have a 10AH battery.

Now if that is like at a 4 hour rate, then 2.5 Amps for 4 hours is 10AH. Your'e exceeding the capacity by a factor of 5 and that gets compounded because it's not at 4 hour rate you are running there. So 16 minutes round trip is about right.

Decrease your losses and use heavy gauge wire everywhere in the power path, eliminate switches and connectors where ever possible. Use an Anderson 100amp power pole connector from the battery and use that to turn the power off by unplugging it.

Or find some place close by that will let you charge it up.

My friends all want me to get a solar jacket, all I need is a sunny day. Too bad the solar jacket is only good for running ipods.

later OM
ray