New ebiker/ebike: Battery help please! (update 10/18)

[Modbikemax]

Honestly guys less is more, the thing is going to weigh a ton with all those batteries and all the beef needed to hold it together not to mention the cost. A modest steady average speed will cover the ground just as quick as great bursts of power intermittently. The guy is 28 and fit as an ox he just wants to get to work a bit quicker, relaxed and less sweaty.

 

[Johnny_Z]

True, I can limit my throttle with my brain and hand control, but it's actually a good point bringing up the controller/CA. When I get this thing put together, I'm going to need to limit the speed to 20 mph. If I get into some accident and the authorities grab my bike and find it can go 24 or 28 mph, I'm in trouble. By limiting it with the CA I hope to avoid legal problems. I'm going to be commuting possibly 300 miles a week with this thing, so something worth considering. Then when I'm having fun on my own time I can open up the controls and let her rip at 28 mph or so.

 

[Johnny_Z]

Honestly guys less is more, the thing is going to weigh a ton with all those batteries and all the beef needed to hold it together not to mention the cost. A modest steady average speed will cover the ground just as quick as great bursts of power intermittently. The guy is 28 and fit as an ox he just wants to get to work a bit quicker, relaxed and less sweaty.

Bingo!

 

[Johnny_Z]

Now considering the Pick and Mix kit from EM3ev as follows:

Controller: 9 fet 30 amp (seems to have the most variety without going overkill)
Motor: 36V 8T upgrade

Not sure about the throttle. Any pros/cons to share regarding half twist vs. full twist vs. thumb?

Not sure about the brakes, especially the HWBS option.

Debating on whether to get the 36V 20Ah or 30Ah from Ping. I have a feeling I'm going to be pissed if I happen to go low, but the price difference is pretty steep, almost $300 difference!

Is it wise to pair Ping battery with EM3 setup? I wish EM3 offered LiFePO4 batteries. Is there anything I need to consider to hook it all up?

Oh, also-I'm hoping to snatch this thing off ebay:

http://www.ebay.com/itm/251667629207?_trksid=p2060778.m1431.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

[wineboyrider]

All the previous posters have given you some really good ideas to start with, but here are 2 more to consider.
1.) A quick place to charge in the middle of the journey. In other words, a really fast 10-15 amp charger whilst your getting a cup of coffee or perhaps a bite to eat. I found a really nice spot on my journey which happens to be right next door to a Sonic drive through. I can stop plug in and by the time I have eaten a burrito or drank my cup of coffee I have added another 500 watt hours into my batteries.
2.) Drag is your number one enemy on a commute like this so there are some ways to make a fairing of sorts to help make your ebike more aerodynamic. This can cut the amount of battery you might need considerably.

 

[Jonathan in Hiram]

What you'll be is pedaling if you go low on the battery with as long a commute as you have.

Stressing out a too-small battery by over discharging it on a regular basis is a quick way to waste some fairly serious money.

 

[danjpendleton]

A good cyclocross bike with a triangle pack from em3ev and a 1000w rear hub motor would fly. if ur running around 20mph u wont need suspension. I avg 20mph on my road bike and commute 14 miles each way to work some days.

I think if u go beach cruiser or mtb bike/fat tires and suspension ur not going to be able to push the distance ur trying to go.

it gets uncomfortable when ur doing 30+ mph on road bikes for a long distance, but if u keep ur speed down and up your front ring gear, reduce ur rear cog....u could make it happen

 

[danjpendleton]

stick with a steel frame and get larger/wider road bike tires and your in the money....if u make it too fast or too heavy ur going to need a rediculous battery for those distances

 

[Johnny_Z]

Well fellas, talked to my boss and I'm gonna be able to charge at work, yay!

Looks like I might also pick up that Giant Cypress Hybrid DX on the cheap as well. Bid is stuck at $69, and this is the second time listed (no bites the first time).

I'm leaning toward going with a complete kit, battery and all, from EM3ev to save on shipping costs and also to make the build a bit easier. I really wanted LiFePO4, but it's starting to look like a costly build and I want to minimize the problems from having parts from 2 different suppliers. With a ~32 mile commute, what do you guys think of this kit from EM3ev? I'm thinking going with the 50 volts 24.8 amp hours battery, should get me 1240 watt hours Plenty right? Any ideas on the the controller type? Is there any particular benefit in having higher or lower amps, or between the "fet" variations? I know I said I didn't want to pedal, but I'm now willing to pedal hills and from a dead stop in order to preserve battery life and longevity.

 

[Johnny_Z]

Awesome boardtrack racer dan. I've already placed my bid for the Giant Hybrid, but if that doesn't work out there is plenty of choice in my local craigslist here.

 

[wesnewell]

What do I think.
http://en.wikipedia.org/wiki/There%27s_a_sucker_born_every_minute
Makes about as much sense as moving to China and then buying what's made there from a US dealer. Nothing wrong with the parts, but by the time you pay shipping, you're going to be out $2K when there's plenty of spots to buy a more reliable DD kit and battery pack in the US for half the price. But since you seem to have lots of money, why not.

 

[Johnny_Z]

American made, better-but where are the batteries? The canadian site doesn't have cheap batteries, they don't even have batteries capable of long distances as far as I know. Every site I've seen has em from China. Your build doesn't look particularly American by the way.

 

[Johnny_Z]

And I'm not getting lipo. Maybe when I'm not living in an apartment building.

 

[Raged]

*old man hat*

It's more important to build something you're happy with and be proud of. Have a design concept with a budget and work towards your goal.

As for buying overseas vs buying locally.... Get whatever is cheaper. Unless someone on the forum wants to pay the difference between buying overseas vs locally "to support local business" it's your money. Do the maths with the total cost (item + delivery) and try to get it all from 1 place to make sure all the plugs fit first time.

 

[danjpendleton]

Em3ev is an excellent choice for your battery. paul is awesome to deal with and his batteries and chargers are top notch. He built me a custom 86v triangle battery with samsung 18650 20R cells 13.3Ah. Its been maintenance free and perfect for my 28 roundtrip commute... At an avg 35-40 mph speed

 

[Johnny_Z]

Hey all once again.

After comparing various kits and combos, motors and batteries, on and on without making any headway I decided to focus on one thing at a time. I think I need to nail the most critical part of my build-batteries. For my commute of 60 miles per day, 5 days a week, 52 weeks a year (likely a bit less, but you get the picture) I'm going to need a top notch battery. Reading here and other forums, it has been recommended over and over to go with em3ev/cell_man/Paul's batteries, and go with A123 at that. I've looked and looked and apparently there aren't anymore A123s in circulation that are "legit." I've checked out em3ev site and he states 500-700 cycles per battery. That's a pretty big let down from what I had been reading regarding A123's fantastic numbers-one poster in a forum cited A123 documents pointing to 3000 cycles and KEEPING 90% capacity. I understand em3ev's batteries are high quality, but I need them to LAST. Ideally longer than a year. "Possibly doubled" through careful charging and discharging seems to me to be a dubious statement. I just don't understand what happened to the technology where LiFePo4 can go a thousand cycles, and A123 can go 3000 cycles, but now our latest greatest get only 500-700 cycles. I know my circumstances create a challenge, but I hope there's something better out there.

So far my 3 candidates are:

Golden Motor 48 Volt, 30 Amp Hour here for $1055 plus shipping.
Ping 48 Volt, 30 Amp Hour here for $1053 plus shipping.
em3ev 50 Volt, 24.8 Amp Hour here for $964 plus shipping.

I believe all of these batteries give me sufficient watt hours to give me a nice cushion so I don't wear out the batteries prematurely. Of these batteries, Golden Motor's has the highest "stated"cycle life at 1200, although Ping's more detailed numbers give 1000 cycles at 85% capacity. em3ev's "possible" 1000-1400 cycles is enticing, and from words spoken here he does seem to understate I'm just wondering by how much. Paul's packs have considerable advantages in price, weight, and placement. I just wish there was some detail to work off of instead of the guesswork number.

Beside the actual battery considerations, em3ev's and Goldenmotor's site offers motors to go with the battery. I'm impressed with both setups in the motor/kit department. Specifically GM's silent Magic Pie 4, though em3ev's MAC kit seems to be a popular standard and is well priced all around from battery to motor.

 

[teslanv]

For my commute of 60 miles per day, 5 days a week, 52 weeks a year (likely a bit less, but you get the picture) I'm going to need a top notch battery.

You are talking about commuting 15,000 miles per year.

You are in Emoto territory there, JZ.

Your Best option would be a custom battery built from the Nissan Leaf Cells. They are 60Ah, and they are BIG, but they would be the only thing I could think of that will have the longevity and range you are after.

http://hybridautocenter.com/HAC4/in...4&name=lithium-batteries-and-packs&Itemid=605

http://endless-sphere.com/forums/viewtopic.php?f=14&t=52162

[edit] For the motor, I think for efficiency and longevity, you will want a slow-wind Direct Drive Hub. Something like a 8X8 9C Clone. (8-turn) and at 36V, you should hit the sweet spot efficiency wise at 18 mph. The 8X8 also has the most copper fill of the 9C clone series, so will be less likely to overheat on the inclines.

 

[Johnny_Z]

Well, those numbers ARE crazy, lol-but I am going to be charging about every 32 miles. I guess I can be the experimental rat here for some of these battery pack claims since I'll probably be going through them faster than most.

 

[wesnewell]

Personally, I'd buy 18 of these,
http://www.hobbyking.com/hobbyking/store/__18631__Turnigy_5000mAh_4S1P_14_8v_20C_hardcase_pack_USA_Warehouse_.html
3 of these,
http://www.hobbyking.com/hobbyking/store/__32032__JST_XH_Parallel_Balance_Lead_4S_250mm_6xJST_XH_.html?strSearch=4s%20balance
and wire them up with a bms for 30ah 12s6p, for ~$500 total. Should be good for 1000 cycles or 3 years, whichever comes first.

 

[BikeFanatic]

Personally, I can recomend the EM3EV kit from paul. I have his 6 fet and 12 fet controller and I use it with a BPM which is a geared motor similar to the MAC. Both work well for me but the 40am 12 fet is a monster. If you are going 30 miles a 50 volt 15 amp hour battery will make it If you stay 20MPH. And a geared motor is much easier to pedal than a Direct drive motor, FYI.
I like his kits as it comes wit the 3 speed switch and intergrated kill swithch and cruise control. I would but a spare throttle with 3 speed switch becasue if you drop the bike the throttle may land first. You may consider an additional controller too.

just my 2 cents

 

[dogman dan]

LOTS of VERY GOOD advice given here already. Including "get a motorcycle"

Figure on 1 ah per mile, for full speed at 36v, or at 48v. You only need a 20 amps controller for cruising 25-30 mph.
But a 30 amps controller is nice when you need a bit more in traffic.

If you will be riding at 30 mph ish, then you will need a really big front gear and a really small back gear to pedal along.
This might be easier for you to make happen, by using a front motor. Then you can keep a good cassette rear wheel.

The bike will have to be able to carry 30 pounds of battery. 48v 30 ah lifepo4. Ping will be fine, just heavy and bulky. So you need a pretty stiff frame. Load up, and weak frames start wagging the tail. A frame able to carry a 48v 15 ah ping in the triangle will help a lot, moving 15 pounds into a better handling location.

Do consider a longtail, or at least a bike intended for touring. At least, you will be packing panniers. Don't fret weight, fret durability on frame and wheels. http://www.ebikes.ca/shop/edgerunner/accessories/x-radical.html

At my age, I NEED full suspension. You might not. But big beach cruiser tires are very good to have.