48V 20ah battery
- Thread starter hulk
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frodus
10 kW
depends on what you need...
how much current peak does it need to be able to discharge?
You could get several Thundersky (cheap right now), some headways, ping, lifebat, PSI.... but all kind of depend on the discharge rating requirements.
how much current peak does it need to be able to discharge?
You could get several Thundersky (cheap right now), some headways, ping, lifebat, PSI.... but all kind of depend on the discharge rating requirements.
I am thinking about going with the rear hub 500W Brushless motor from ampedbikes. From what I understand this is how the battery breakdown goes:
36V = 22-23mph
48V = 27-28mph
20ah = 30-40 miles
10ah = 15-30 miles
Based on this I came to the conclusion that the 48V 20ah battery is the one I will most likely need. However, to answer your question, I have no idea what the discharge rating requirements are. I'm thinking I could go with either the 48V 20ah or the 36V 20ah battery. Can someone please list how much each of the 4 battery configurations costs and weighs so I can better judge which one I really need. The 48V 20ah battery weighs in at 25lbs, correct?
36V = 22-23mph
48V = 27-28mph
20ah = 30-40 miles
10ah = 15-30 miles
Based on this I came to the conclusion that the 48V 20ah battery is the one I will most likely need. However, to answer your question, I have no idea what the discharge rating requirements are. I'm thinking I could go with either the 48V 20ah or the 36V 20ah battery. Can someone please list how much each of the 4 battery configurations costs and weighs so I can better judge which one I really need. The 48V 20ah battery weighs in at 25lbs, correct?
frodus
10 kW
You didn't tell us what the PEAK requirement for current is.... If I assume 500W is the peak of the motor (which isn't much), thats only about 10-15A on the battery pack... so batteries with 1-2C ratings would be fine at 48V 20Ah.
Go to the battery technology forum and do some researching, alot of other newbies come here asking the same thing.... each of them with a different setup, half the project occurs in the design, the rest in implementation. You're going to have to do some shopping around.... Each of those batteries I listed is a differeny type and shape. You'll also have to contact the manufacturer of the batteries to get current pricing. This isn't walmart if thats what you're wanting...
If you want, You can pay me to do it for you...... I'm a consultant for 2 other companies and 2 private people.
Go to the battery technology forum and do some researching, alot of other newbies come here asking the same thing.... each of them with a different setup, half the project occurs in the design, the rest in implementation. You're going to have to do some shopping around.... Each of those batteries I listed is a differeny type and shape. You'll also have to contact the manufacturer of the batteries to get current pricing. This isn't walmart if thats what you're wanting...
If you want, You can pay me to do it for you...... I'm a consultant for 2 other companies and 2 private people.
dogman dan
1 PW
Define best deal. If the best deal is less middlemen marking an item up, and a quality product, go to pingbattery.com. His packs will easily power an ampedbikes motor. There are lots cheaper ones on ebay, but the cells are not the same and in some cases customer service has not been good. Ping has the rep for good reliability and excellent customer service.
The headway packs are still pretty new, but seem to be the best option now for higher discharge rates using more powerfull motors. Lucky canadians just go to canadian tire for yardworks battery packs.
The headway packs are still pretty new, but seem to be the best option now for higher discharge rates using more powerfull motors. Lucky canadians just go to canadian tire for yardworks battery packs.
Thanks for the info. The peak power of that motor is 700 watts. I really like ping's prices but still unsure which battery to go with. I don't know if I want speed or distance...or both. The 36V 10ah looks like the best deal for $300 with a range of 15-30 miles (with pedaling of course). The general rule is 1ah = 1 mile yes? So without any pedaling that battery would go just 10 miles, which is fine since I live only 7 miles from work. But my question is, what is the best way to charge these batteries? Is it ok to discharge them all the way? Is it ok to discharge them 80% of the way and then not charge them immediately, maybe wait 5 or so hours? .
tostino
10 kW
1ah != 1 mile. Amp hours does not compute directly into mileage. Watt hours can be used to see how many miles pr unit of energy you can go.
So a 48v 20ah battery has 960 watt hours (48 * 20 = 960). A bike going roughly 25mph unassisted will use roughly 20-25wh/mile. So if you get 20wh/mile, the bike will go 48 miles pr charge. If it gets 25wh/mile it will go 38 miles pr charge.
Speed is dependent on motor characteristics and battery voltage. On some motors, you will go 20mph on 48v, on others you will go 30mph on 48v.
So a 48v 20ah battery has 960 watt hours (48 * 20 = 960). A bike going roughly 25mph unassisted will use roughly 20-25wh/mile. So if you get 20wh/mile, the bike will go 48 miles pr charge. If it gets 25wh/mile it will go 38 miles pr charge.
Speed is dependent on motor characteristics and battery voltage. On some motors, you will go 20mph on 48v, on others you will go 30mph on 48v.
dogman dan
1 PW
I like to say 1 ah per mile at 36v, because my real world ride sometimes uses that much. It's not intended to mean you have to have that much. Just that it's SMART to have that much. Once in awhile, my 15 miles of uphill all the way home has a 40 mph headwind. On that day, I might need 1.5 ah per mile. Most days I get home on about .8 ah per mile, and if I have a tailwind of 40 mph, a lot less. Sure, most rides have less wind or hill to deal with. My route happens to follow a hilltop alongside the highway so there is no trees or houses to hide behind. Anyway, the battery will last longer if it has less stress on it so having the absolute minimum is not so smart in my opinion. A pingbattery 10 ah v3 should be plenty able to supply that motor if you have a flatter ride, but I still like the idea of a 15 or 20 ah pack for hills if you have them. The 1 ah per mile figure is just a very round number that can accept a lot of varaitions from the rider, like 300 pound weight, or 20 psi tires, or 800 ft of vertical gain without being totally wrong on the not enough side. This number is also based on no pedaling to start up, and riding full throttle with minimal pedaling effort. Obviously, if you pedal first a few hundred feet, and ride 3/4 throttle most of the time, you will use a whole lot less than an amp hour per mile. More like .5 ah. Not all of us want to calculate down to the last watthour. We just want a ballpark figure on what size would get me there, or there and back. This figure works on lithium or nicad batteries, not sla's, and is for bikes with speeds in the 20-25 mph range at 36v. Obviously motors wound different will perform different. This number of 1 ah per mile incudes a health reserve so you don't arrive at work with the bms tripping every day, and is way too much battery if you intend to ride less than 20-25 mph.
With a pingbattery, you don't need to charge right away, and the bms should stop you from discharging to the point where the cells get damaged. So you can ride to work, not charge, and ride back if you have the big enough size for that. Carrying the thing is another story. 48v-20 ah packs get a bit on the heavy side, and the package doesn't fit so good on the bike anymore. 36v-20 ah or 48v-15 ah packs will take you 20-25 miles minimum and still fit on a bike rack pretty nice. If you have a flat ride, a 36v 10 ah should be all you need, but having more is real nice. I'd buy enough to get to work and back so you don't have to bother with charging there, and then you have the capacity for longer weekend rides. It's a lot of money, but my pingbattery is the only ebike thing I have bought in the last year that has worked flawlessly for the entire year. Hopefully my brushless aotema motor will not give me trouble in the hot summer like the brushed ones did last year. But anyway, the pingbattery I bought a year ago has proven to be the cheapest per mile thing I have.
With a pingbattery, you don't need to charge right away, and the bms should stop you from discharging to the point where the cells get damaged. So you can ride to work, not charge, and ride back if you have the big enough size for that. Carrying the thing is another story. 48v-20 ah packs get a bit on the heavy side, and the package doesn't fit so good on the bike anymore. 36v-20 ah or 48v-15 ah packs will take you 20-25 miles minimum and still fit on a bike rack pretty nice. If you have a flat ride, a 36v 10 ah should be all you need, but having more is real nice. I'd buy enough to get to work and back so you don't have to bother with charging there, and then you have the capacity for longer weekend rides. It's a lot of money, but my pingbattery is the only ebike thing I have bought in the last year that has worked flawlessly for the entire year. Hopefully my brushless aotema motor will not give me trouble in the hot summer like the brushed ones did last year. But anyway, the pingbattery I bought a year ago has proven to be the cheapest per mile thing I have.
Thanks for the useful information! I was thinking of going with the 36V 10ah battery but after reading your post I am really thinking about going with the 15ah version, you're right about always having extra battery life in case I need it. The ping 15ah version is only 4 pounds heavier than the 10ah version. I'm thinking about selling my car, or at least putting it in storage, and using my bike as the my main transportation. I'm in fairly good shape and I do enjoy biking. So my main purpose of turning my bike into an ebike is not to turn it into a scooter/moped/motorcycle but to have a little "assistance" once in a while, mainly when going in to work so I don't get all sweaty.
Currently my average speed is 12mph and max was 18mph on a heavy 37lb mountain bike with fat 2.1" tires. With the battery and some thinner 1.75 I hope to get better speed with a little less work. I was originally going to buy the $300 walmart ebike which comes with a 450w motor and a 24V/10AH battery pack because it looked like the best bang for the buck until I realized that the battery lasts only 500 miles until you have to buy another one for $110 which makes it as expensive as owning a beater car. I'd like to get the 48V 15ah battery but there's a point when the ebike would become a hobby and not as a way of saving money. If people are riding their 24v 10ah 90 pound walmart ebike to work than I can surely do fine on my 36v 15ah 60lb bike!
Now, the only question is can someone validate my decision! Once I buy the 36V 15ah battery it will be at least 3 years until I can replace it! I'm worried that if I get it a few weeks later I will want the 48v version!
So for those of you that own a 36v battery, do you ever wish that you went with the 48v version? Do you think an extra couple mphs are worth it?
EDIT: Actually I am now considering "upgrading" from the 36v 15ah to the 48v 15ah ping battery for only $100 more. On his website it says that the batteries can be recharged 1,000-3,000 times. So even if the battery was to be charged once a day it would take 3 years to reach 1,000 cycles. Also, he charges $100 for shipping so it's best to buy the right battery the first time.
Currently my average speed is 12mph and max was 18mph on a heavy 37lb mountain bike with fat 2.1" tires. With the battery and some thinner 1.75 I hope to get better speed with a little less work. I was originally going to buy the $300 walmart ebike which comes with a 450w motor and a 24V/10AH battery pack because it looked like the best bang for the buck until I realized that the battery lasts only 500 miles until you have to buy another one for $110 which makes it as expensive as owning a beater car. I'd like to get the 48V 15ah battery but there's a point when the ebike would become a hobby and not as a way of saving money. If people are riding their 24v 10ah 90 pound walmart ebike to work than I can surely do fine on my 36v 15ah 60lb bike!
Now, the only question is can someone validate my decision! Once I buy the 36V 15ah battery it will be at least 3 years until I can replace it! I'm worried that if I get it a few weeks later I will want the 48v version!
So for those of you that own a 36v battery, do you ever wish that you went with the 48v version? Do you think an extra couple mphs are worth it?EDIT: Actually I am now considering "upgrading" from the 36v 15ah to the 48v 15ah ping battery for only $100 more. On his website it says that the batteries can be recharged 1,000-3,000 times. So even if the battery was to be charged once a day it would take 3 years to reach 1,000 cycles. Also, he charges $100 for shipping so it's best to buy the right battery the first time.
wakataka
10 mW
- Joined
- Jul 28, 2008
- Messages
- 25
I'd go with the 48v. I have both 36 and 48v SLA packs. I find I don't use much more Wh/mile with the 48v pack because I generally just cruise at 20 - 25 mph and I don't need full throttle to do that with the 48v pack. But with 36v I run near full throttle on the flats and need to downshift on some of the hills on my route. With 48v, I can stay in high gear the whole way. My commute is only ~3 miles each way and I can charge at work, so SLA works just fine for my needs, except for being heavy.
I use about 15 Wh/mile on my relatively flat commute, cruising at 20+ mph with moderate effort. When it gets above 100f, I tend to pedal a little less and use a little more watts. But I can get to my destination with a minimum of sweat and no need to change clothes. It's a dry heat, here in Nor Cal.
I use about 15 Wh/mile on my relatively flat commute, cruising at 20+ mph with moderate effort. When it gets above 100f, I tend to pedal a little less and use a little more watts. But I can get to my destination with a minimum of sweat and no need to change clothes. It's a dry heat, here in Nor Cal.
dogman dan
1 PW
I agree. get the 48v, but be sure the motor controller you choose is really designed for 48v. Lots of us run 48v though 36v controllers and get away with it, but some don't get away with it. The 15 ah 36v is a bit small in my opinion, allowing a 20 mile ride at 18- 20 mph perhaps, which means 10 out and 10 back is the limit without charging. You'd be suprised how limiting that can be. the 36v 20 ah or the 48v 15 ah will take you at least 13 out and 13 back, which may be a big difference when trying to live car-less. In my big sprawling westen town, I would need 30 ah of 36v to be able to go to work and back without charging.
Anyway, 15 pounds of pingbattery will give you some real range, and allow really long rides on the weekends when you have the time to ride slower. the 48v version will have a bit more pep when you need it, like a hill. The better acceleration is noticeable, but not better enough to save you life or anythting. I have often wished I had gotten the 48v 20 ah, but then, I am also glad to have a bike that I can claim to be legal too. The need for that hasn't come up, but if it does, I can lie about it a bit easier with a 23 mph bike than I could with a bike that did 27 mph or more. 36v gets me up steep hills just fine but it is nice on the same hill to have 48v
.
Either battery, 36-20 or 48-15 is the same physical size and has the same number of cells. They fit nice in old steel toolboxes on a rear rack.
Anyway, 15 pounds of pingbattery will give you some real range, and allow really long rides on the weekends when you have the time to ride slower. the 48v version will have a bit more pep when you need it, like a hill. The better acceleration is noticeable, but not better enough to save you life or anythting. I have often wished I had gotten the 48v 20 ah, but then, I am also glad to have a bike that I can claim to be legal too. The need for that hasn't come up, but if it does, I can lie about it a bit easier with a 23 mph bike than I could with a bike that did 27 mph or more. 36v gets me up steep hills just fine but it is nice on the same hill to have 48v
.
Either battery, 36-20 or 48-15 is the same physical size and has the same number of cells. They fit nice in old steel toolboxes on a rear rack.
jimw1960
10 kW
I agree with dogman on the pingbattery recommendation for your needs. It is a good mid-grade battery that can handle 2C current draw if needed. I think the 1Ah per mile recommendation is a bit conservative for most needs--dogman has a serious hill to pull on his commute. I recently upgraded to a 48v/20Ah ping and commute 30 miles round trip on it several times a week and never come close to low-voltage cutout. The 48v system will take you faster than you can pedal on that system, so if you are really only looking for assist, a 36v system will do. My last battery was a 36v/15Ah cheap duct-tape battery off ebay and I could still pedal along at the speed that one would go with a 20amp controller. I regularly got over 25 miles on that, but it would usually cut out before the end of my 30-mile commute.
Christobel931
100 mW
In my opinion, you might be kicking yourself if you don't get the 48v. You can always dial back the speed a little to maintain a comfortable pedal cadence.
I think a lot of folks around here have tried to save a few bucks in the beginning, only to spend many times more later in upgrades... don't ask how I know this. :wink:
I think a lot of folks around here have tried to save a few bucks in the beginning, only to spend many times more later in upgrades... don't ask how I know this. :wink:
