dnmun
1 PW
don't buy that Vpower battery pack.
don't buy that Vpower battery pack
nonononononononono
don't buy that Vpower battery pack
nonononononononono
Newbue wants to build an ebike
- Thread starter johnjapan
- Start date
Cuz they can have serious hidden problems within them. Search on Vpower, Volgood, here on ES, and you will find a number of posts and threads about the issues.
Many packs may be fine, but you probably won't know if yours has a problem until it is too late to do much about it besides take it apart and repair it yourself.
Many packs may be fine, but you probably won't know if yours has a problem until it is too late to do much about it besides take it apart and repair it yourself.
miro13car
100 kW
Johnjapan
I would suggest you different approach
You can read and read and what?
What you need is a riding experience on several bikes
Some shout WOW riding Currie crap ebike and call it good ebike
Simple you must try the worst and the best in ebike category
you choose
I would suggest you different approach
You can read and read and what?
What you need is a riding experience on several bikes
Some shout WOW riding Currie crap ebike and call it good ebike
Simple you must try the worst and the best in ebike category
you choose
miro13car said:
The simulator and the forums have given enough info for me to make an informed decision
I'm going with a 48v15ah battery, I have no idea on how to decide which motor im reasearching...
300w 500w 750w 1000w motors which one is ideal for the battery I've chosen? I'd like to also have my gears operational for normal pedaling its an interesting predicament.
Chalo
100 TW
johnjapan said:
Okay, so you have a battery in mind. Find out what its real limitations (as opposed to its manufacturer spec sheet limitations) are. Mostly you need to find out how much current it is good to deliver continuously, and still have the lifespan you expect.
Then you'll need to find a controller that is good for at least that much voltage, but which delivers no more current than is healthy for the battery to provide.
Then you'll need to find a motor that operates efficiently within the power range your controller supports, and runs at the speeds that you can actually reach with that much power.
Using a recent version of the Cycle Analyst allows you to mismatch stuff (for instance using a controller and motor too big for your battery, which could play with a more potent battery in the future) without beating up your components. It allows you to set current limits, speed limits, etc. to protect the weakest parts of your system.
Generally speaking, if you want the simplest system possible-- without a Cycle Analyst-- get more battery (in terms of maximum power) than your controller needs, and more motor than your controller implies. That way, the controller is the power bottleneck, the motor stays relatively cool and efficient, and the battery lasts a long time. You'll be able to use all the amps your controller can supply through most of the motor's speed range, rather than a just-enough motor causing power to taper off early.
DAND214
10 MW
As Dnmun said no VPOWER!
They are over rated and have a million welds that break.
If you want 15Ah you better buy a 20Ah pack, cause they are mostly rated about 25% over what they are.
BEEN THERE DONE THAT! Not again!
Dan
They are over rated and have a million welds that break.
If you want 15Ah you better buy a 20Ah pack, cause they are mostly rated about 25% over what they are.
BEEN THERE DONE THAT! Not again!
Dan
dogman dan
1 PW
Yes, in the past the vpower brand packs were made from a large number of 18650 round cells. The problem was not so much the cells but the not so great assembly of them. Typically dropping the pack would result in a few spot welds that connect the cells popping. Every disconnected cell in the pack resulted in less capacity. Bear in mind, the delivery system involves repeated drops of the package. Very typical was for a pack to arrive with 5 ah less capacity than you paid for.
Pingbattery and others use a pouch cell, that is a bit less likely to have this problem, since they use soldered connections on pouch cells.
48v 15 ah lifepo4 will typically run a 20-25 amps controller just fine. It can run a 30 amps, but it may wear out quicker if you actually pull that 30 amps very often riding it. Find out what the actual amps of the controller is, don't go by wattage, which can mean anything the marketers feel like it being. You need something in the 15-25 amps range. More amps will just cost you distance. 48v battery with a typical 20 amps controller will give you a real world 1200 amps avaliavble, since the controllers are often actually 22 amps.
A planetary gearmotor can help if you break down. Much less resistance from the motor when just pedaling. But aside from disconnected wiring which is field fixable, direct drive motors are pretty dang reliable in normal road use. More likely is a battery problem. If you are charging at work, you won't be so likely to have that problem. If you do, finding out about it is crucial. If you can save back 1/6th of your capacity, you can ride at 100w power for one hour and make it home with no motor drag.
I just personally have come to prefer direct drive motors because I live in a seriously hot climate, and dd cools itself a bit faster when I need to stop to let a motor cool. But many really really like Mac and BMC planetary gearmotors. Other smaller motors such as the bafang and cute can work for you as well, but if you are limited to 500w, then you will be slowed down a lot by hills and headwinds. Again, I prefer a stronger motor at times. I sometimes ride home uphill into a lot of wind.
Pedaling, yes it's true I don't pedal like I used to because I got sick. But I still give range advice assuming that you will pedal with moderate effort. It doesn't add much range unless you are riding slow. Not pedaling hard, just enough to add 1 mph to your speed at 20 mph. At 15 mph, it might add 3 mph though.
FWIW, 20 mph with no pedaling on flat ground takes about 400w for upright bikes. About 10 amps from the 48v 15 ah battery, and plenty under the batteries limits of about 30 amps max.
Pingbattery and others use a pouch cell, that is a bit less likely to have this problem, since they use soldered connections on pouch cells.
48v 15 ah lifepo4 will typically run a 20-25 amps controller just fine. It can run a 30 amps, but it may wear out quicker if you actually pull that 30 amps very often riding it. Find out what the actual amps of the controller is, don't go by wattage, which can mean anything the marketers feel like it being. You need something in the 15-25 amps range. More amps will just cost you distance. 48v battery with a typical 20 amps controller will give you a real world 1200 amps avaliavble, since the controllers are often actually 22 amps.
A planetary gearmotor can help if you break down. Much less resistance from the motor when just pedaling. But aside from disconnected wiring which is field fixable, direct drive motors are pretty dang reliable in normal road use. More likely is a battery problem. If you are charging at work, you won't be so likely to have that problem. If you do, finding out about it is crucial. If you can save back 1/6th of your capacity, you can ride at 100w power for one hour and make it home with no motor drag.
I just personally have come to prefer direct drive motors because I live in a seriously hot climate, and dd cools itself a bit faster when I need to stop to let a motor cool. But many really really like Mac and BMC planetary gearmotors. Other smaller motors such as the bafang and cute can work for you as well, but if you are limited to 500w, then you will be slowed down a lot by hills and headwinds. Again, I prefer a stronger motor at times. I sometimes ride home uphill into a lot of wind.
Pedaling, yes it's true I don't pedal like I used to because I got sick. But I still give range advice assuming that you will pedal with moderate effort. It doesn't add much range unless you are riding slow. Not pedaling hard, just enough to add 1 mph to your speed at 20 mph. At 15 mph, it might add 3 mph though.
FWIW, 20 mph with no pedaling on flat ground takes about 400w for upright bikes. About 10 amps from the 48v 15 ah battery, and plenty under the batteries limits of about 30 amps max.
lbz5mc12
10 kW
Maybe this will help for ideas. I currently have an e-bikekit rear DD hub kit on my GT. I'm using 2 bmsbattery.com batteries. I have a 36V 20Ah and a 48V 10Ah both lithium ion. The 36V pack with shipping to the US was $390.00 and the 48V was $326.00. I got a good deal on my kit and only paid $375.00 from a local dealer. That puts me at $1,091.00 so far. I've previously owned the cheaper yescom style hub kits both 500W/800W. I got about 20 mph out of the 500 and 27 mph out of the 800. Usually if you check ebay you can find the cheaper kits with free shipping. I know a lot of the ES members boohoo the bms batteries but I've had no problems with mine. I'd have to say on my current set up I could, with moderate pedaling, get about 30 Miles out of my combined packs. My total rider + bike weight is well over 400 lbs. So if you're a skinny minny you could easily pull off 40 miles with my set up. My 36V battery puts me at 20 mph which is the legal limit in California and the 48V is more for off road at 28 mph. Currently my packs are on the back while I'm researching mid mount options. If anyone could recommend a fairly priced mid mount bag it would probably help me and John. So um yeah okay.
lbz5mc12
10 kW
They sell expensive mid mount bags on hi-powercycles.com. I know someone had a thread somewhere about good but cheaper priced bags.
borschelrh
10 W
Don't forget John is living in Japan so US prices, availability, and options don't apply. He is better off buying either in Japan or from China but I don't know the customs duties issues from China to Japan. Given the current political crisis over the islands between China and Japan this may actually be a problem.
Dogman's advice is sound. Greenbikekit has some geared hub motors at attractive prices as well. I do agree a cycle analyst makes a lot of sense and I do agree limiting the controller is the wisest way to go about this. Personally, I don't like to go faster than 30 kph on a bicycle so limiting the speed is fine with me. I also pedal roughly 75% of the effort. The kit I am using has a small LCD panel mini-controller which reads the speed from a wheel sensor and the input from the pedal sensor to control the speed. It also limits the voltages. I can tell when it is set for 25 kph and I pedal a bit faster and the motor cuts out exactly how much effort is required to maintain my speed and how much I am contributing myself. This goes a long way to increase range in the flats. Hills are a different challenge and can stress the system. All of it is a trade off. I do think it wise to get a 48v system and I would shot for an 800 or higher watt motor. The windings of the motor are also important and I am no expert but I think Dogman has that figured out well. I would have gone with a geared hub motor but I ride primarily off road and this is bad for gears.
Dogman's advice is sound. Greenbikekit has some geared hub motors at attractive prices as well. I do agree a cycle analyst makes a lot of sense and I do agree limiting the controller is the wisest way to go about this. Personally, I don't like to go faster than 30 kph on a bicycle so limiting the speed is fine with me. I also pedal roughly 75% of the effort. The kit I am using has a small LCD panel mini-controller which reads the speed from a wheel sensor and the input from the pedal sensor to control the speed. It also limits the voltages. I can tell when it is set for 25 kph and I pedal a bit faster and the motor cuts out exactly how much effort is required to maintain my speed and how much I am contributing myself. This goes a long way to increase range in the flats. Hills are a different challenge and can stress the system. All of it is a trade off. I do think it wise to get a 48v system and I would shot for an 800 or higher watt motor. The windings of the motor are also important and I am no expert but I think Dogman has that figured out well. I would have gone with a geared hub motor but I ride primarily off road and this is bad for gears.
lbz5mc12
10 kW
Correct me if I'm wrong but I'm assuming Japan would be a nation with a lot of EV options. I understand what you mean by shipping issues to Japan. I think if it was coming from the US it wouldn't be a big issue but China on the other hand......?
borschelrh
10 W
http://www.customs.go.jp/english/tariff/2012_1/index.htm lists the official import duties. It is a serious consideration when buying stuff outside your country and something nearly absent in the US now for some very stupid reasons. It used to be that import duties were the main source of revenue in the US but later this week the very last set of countries will become duty free when the US signs the free trade agreement with the EU. This is the main reason jobs and manufacturing have left the US. It is cheaper to put hire foreigners for slave wages to make cheap junk for sale in the US. There is no incentive now to make anything in the US at all. Dumb! Just so people can have cheap garbage at the expense of the entire economy.
lbz5mc12
10 kW
I know what you mean. The big problem is that there is actually a lot of good stuff being shipped in with all the crappy stuff and it all seems to get lumped into the crappy category. I hate that we've become a distributor for the rest of the world's merchandise. It's just too depressing to even try to type up my thoughts and feelings on the sorry state my country's in. I feel like we're in another gilded age; shiny on the outside and rotten in the core.
borschelrh
10 W
I made a mistake on the agreement. They are signing an agreement to meet and make an agreement. So, it still has a long ways to go. This impacts on the US automobile manufacturers as it means an immediate decrease in prices for European manufactured autos which is pretty much a one way street from Europe to the US. Few in Europe are eager to buy American made vehicles which are arguably far inferior. I was back in the US last year and rented a Chrysler 500 which had less than 1,000 miles on it and my foot went through the floor and I could see the road beneath. The metal cut my leg when it happened so crap is still crap in the US. Just saying.
borschelrh said:
A very excellent method of control where it calculates you're effort and compensates according to a set cruise speed
what is this feature called if I wanted to make sure it was included in my purchase of an ebike kit?
i'm not sure if you're aware guys but there's a site called alibaba.com
where you can purchase direct from China straight from the factory. The site has a lot of ebike kits and batteries but you're dealing with people that can only handle very simple English most times.
Since I live in japan I think that's my best option
shipping to and from Japan between China should be ok despite the fight over a piece of rock.
Japan hasn't been as aggressive as China on the production of these new lifepo4 batteries available to the open public
if I build this ebike guys I'll essentially be the only one in town let alone province that will have one of these. Of course I'm not here to flash it I sincerely need this bike for practical use to travel to and from work with fun riding on weekends.
I don't want un wanted attention from the police so Ill be as discreet as possible.
where you can purchase direct from China straight from the factory. The site has a lot of ebike kits and batteries but you're dealing with people that can only handle very simple English most times.
Since I live in japan I think that's my best option
shipping to and from Japan between China should be ok despite the fight over a piece of rock.
Japan hasn't been as aggressive as China on the production of these new lifepo4 batteries available to the open public
if I build this ebike guys I'll essentially be the only one in town let alone province that will have one of these. Of course I'm not here to flash it I sincerely need this bike for practical use to travel to and from work with fun riding on weekends.
I don't want un wanted attention from the police so Ill be as discreet as possible.
Drunkskunk
100 GW
johnjapan said:
Yes.. we are very aware... There are some honest people who use alibaba. BUT there is a Huge number of fraudlent listing, and scamers who use it as well. It is easy to spot some, but impossable to spot them all. We've had a few threads about the issue here. I believe one member here had their bike's picture being fraudlently used in an add for one vendor.
Basicly, you are gambling when using Alibaba, and the risk is great of losing your money.
There are better options.
For batteries, we colectivly trust Mr Ping of Ping battery. and Paul of em3ev.com for low cost but reliable quality with excilent customer service. em3ev.com would also be a safe place to get your other parts in Asia. anyone else I can recomend is in north america, so shipping would be more.
lbz5mc12
10 kW
Are there a lot of scammers on dhgate.com too? I purchased a battery from a seller on there and had all kinds of problems with it. I haven't bought anything through them since. On a side note you might want to check out bmsbattery.com. They have really good prices and all my packs from them have worked great. They are a Hong Kong dealer.
If there is a place where sellers gather, there are a lot of scammers. If not when it's first founded, it won't take long. I give any new place a week before the first scammers show up.
borschelrh
10 W
John,
Sorry I didn't catch up on posts recently. There are a couple of ways to control the assist. The method my kit used and is the most common is called pedelec in which there is a magnetic sensor that mounts to the bottom bracket and measures pedal rotation. It is merely reading on or off and if you are pedaling the motor kicks in to keep the bike at a set speed which is measured using a speed sensor mounted to the wheel. This is the most common and cheapest method. A better system is to measure torque (torque sensing) and the motor assists as needed based on the torque contributed by the rider. Both seem to work but I have only used the pedelec system. I do have the option of setting the controller to a zero setting which then turns of the speed setting altogether and the motor is controlled by throttle alone. This also works well and bypasses the pedelec altogether. My LCD controller allows me to set the maximum speed at the highest of the 5 settings to 40 kph and the remaining settings are ratios (not sure exacly what they are) but with the max at 40 the minimum at setting 1 is 25 kph. If I am riding on flats or roads I use this setting. In real terms I don't ever see 40 kph but I do get 30 kph without problem. Probably if I were running at 48V I might be able to get higher speeds but as I said before I like riding at a max of 25 kph and it gets better range and is not so rough on the wheels. I have been riding a lot lately and I still haven't depleted the battery more than 1/2 even riding 60 kilometers. But, I am doing most of the pedaling. I do notice that there is appreciable motor sag when the battery is at 1/2 capacity when I am going up hills so perhaps I am closer to the limits of the battery than I think. Without a Cycle Analyst I can't really say for sure and I am not eager to spend $200 here in Europe to get one. I may order one from the US if one of my relatives comes this Summer.
I would look at TaoBao if you aren't going to use one of the recommended sellers. Google does a pretty good job translating the Chinese and Mr Tao seems to be okay for the actual purchases but again, I haven't needed to try it yet. I would look very hard inside Japan and see if there are some reasonable sellers. I did this in Europe and finally found the Czech site who don't gouge their customers. Prices here in Hungary are ridiculous but I found a guy in Italy that is reasonable and another in France as well. The Czechs were the lowest price and I am satisfied.
Sorry I didn't catch up on posts recently. There are a couple of ways to control the assist. The method my kit used and is the most common is called pedelec in which there is a magnetic sensor that mounts to the bottom bracket and measures pedal rotation. It is merely reading on or off and if you are pedaling the motor kicks in to keep the bike at a set speed which is measured using a speed sensor mounted to the wheel. This is the most common and cheapest method. A better system is to measure torque (torque sensing) and the motor assists as needed based on the torque contributed by the rider. Both seem to work but I have only used the pedelec system. I do have the option of setting the controller to a zero setting which then turns of the speed setting altogether and the motor is controlled by throttle alone. This also works well and bypasses the pedelec altogether. My LCD controller allows me to set the maximum speed at the highest of the 5 settings to 40 kph and the remaining settings are ratios (not sure exacly what they are) but with the max at 40 the minimum at setting 1 is 25 kph. If I am riding on flats or roads I use this setting. In real terms I don't ever see 40 kph but I do get 30 kph without problem. Probably if I were running at 48V I might be able to get higher speeds but as I said before I like riding at a max of 25 kph and it gets better range and is not so rough on the wheels. I have been riding a lot lately and I still haven't depleted the battery more than 1/2 even riding 60 kilometers. But, I am doing most of the pedaling. I do notice that there is appreciable motor sag when the battery is at 1/2 capacity when I am going up hills so perhaps I am closer to the limits of the battery than I think. Without a Cycle Analyst I can't really say for sure and I am not eager to spend $200 here in Europe to get one. I may order one from the US if one of my relatives comes this Summer.
I would look at TaoBao if you aren't going to use one of the recommended sellers. Google does a pretty good job translating the Chinese and Mr Tao seems to be okay for the actual purchases but again, I haven't needed to try it yet. I would look very hard inside Japan and see if there are some reasonable sellers. I did this in Europe and finally found the Czech site who don't gouge their customers. Prices here in Hungary are ridiculous but I found a guy in Italy that is reasonable and another in France as well. The Czechs were the lowest price and I am satisfied.
