building my first e bike

[wesnewell]

That's 264wh per battery, so a total of 792wh. Now cut that in half because of sla properties and you'll have ~400 usable wh. Should get close to 20 miles out of it. BTW, your controller will be 30A. So you need a battery that will put out that many amps without damage to it. That pretty much eliminates all those small bottle batteries.

 

[lbz5mc12]

Are you sure about that because the Currie controller on my roommate's bike is 30A and it works fine. It's all dependent on how much throttle you give the motor.

You know if I knew where you were and if you were able to pick them up I've got a 36V 15A and a 36V 12A SLA battery pack sitting in my garage plugged into their chargers that I have no use for. They are wrapped in thermal duct tape and they are each in their own battery bag. I'm in California but knowing my luck you're probably all the way on the other side of the country.

 

[wesnewell]

Please go to the User Control Panel, select Profile, and then enter your city, state/province, and country into the Location field (country minimum) and save it. This will help people help you. Example: Wylie, TX, USA. Without knowing what country you are in it's hard to make any recommendations. Thank you.

 

[ken1645]

Please go to the User Control Panel, select Profile, and then enter your city, state/province, and country into the Location field (country minimum) and save it. This will help people help you. Example: Wylie, TX, USA. Without knowing what country you are in it's hard to make any recommendations. Thank you.

Wes, not sure if you'll find this funny or not but when I first saw you post this I totally thought you were a bot that posts this anytime someone posts something that doesn't have their location set in the control panel

That said, it does help when people clarify their location.

 

[wesnewell]

Maybe I'll just start doing it this way.
http://endless-sphere.com/forums/viewtopic.php?f=3&t=26488&p=717771#p717771
****Do this before your first post or now (it's retroactive)*****
Please go to the User Control Panel, select Profile, and then enter your city, state/province, and country into the Location field (country minimum) and save it. This will help people help you. Example: Wylie, TX, USA. Without knowing what country you are in it's hard to make any recommendations and you will waste your time and others. Thank you.

 

[amberwolf]

what im really trying to do is make a bicycle i can ride about 40 miles without recharging it would mostly be used going on flat terrain sidewalk at cruising speed of 15 to 20 mph and it would probablly never get taken 40 miles on a single charge at best i might use 20 miles for a round trip

At a guess, a pack to do 40 miles at those speeds without a recharge, in SLA, is going to weigh around 100lbs, based on my own experiences with it, evne if you provide some of the power by pedalling.

If you are doing a lot of stops and starts, it's worse, especially with a heavier pack, becuase even more energy is wasted getting it all moving again, and it's wasted at the higher loss rate (see Peukert Effect) as well.

So while SLA can be practical, it may not be for what you want to do.


Also keep in mind that if you go the route I suggested for used SLA, they're probably only going to have 1/4 to 1/2 of their capacity available, at best, so that makes your pack twice to four times as large (and heavy) to do the same job.

 

[lbz5mc12]

One thing to add is that you never want to "not" charge your battery after every use. When you let it run down all the way before you recharge it'll shorten the lifespan/charge cycles of the pack. Every time you use it whether it's 10 miles or 2 you need to plug it back into the charger asap.

 

[amberwolf]

That's true, (for SLA) and I forgot to add that to my post above. Thank you for pointing that out!

 

[mrfeelgooddrag26]

http://www.ebay.com/itm/12V-9Ah-Lithium-Iron-Phosphate-LiFePO4-SEALED-Battery-w-PCM-/181065132268?pt=US_Rechargeable_Batteries&hash=item2a2852a8ec

i was thinking about buying 4 of these for my bike ive heard there almost as good as lipo and way better than lead acid my question is are they worth the price in terms of how much range they will yeild for my ebike? lets be real here its 9 amp hours a battery so 36 total amp hours right? times that by 48 volts for the motor and you get 1728 watt hours divide that by 40 for each mile and its 43.2 miles??? even at 60 watts a mile its still 28.8 right??

so my question is will these batterys perform good for my setup and are they worth the cost and have you guys ever used these kinds of batterys?

 

[Takemehome]

http://www.ebay.com/itm/12V-9Ah-Lithium-Iron-Phosphate-LiFePO4-SEALED-Battery-w-PCM-/181065132268?pt=US_Rechargeable_Batteries&hash=item2a2852a8ec

i was thinking about buying 4 of these for my bike ive heard there almost as good as lipo and way better than lead acid my question is are they worth the price in terms of how much range they will yeild for my ebike? lets be real here its 9 amp hours a battery so 36 total amp hours right? times that by 48 volts for the motor and you get 1728 watt hours divide that by 40 for each mile and its 43.2 miles??? even at 60 watts a mile its still 28.8 right??

so my question is will these batterys perform good for my setup and are they worth the cost and have you guys ever used these kinds of batterys?

In serie voltages add up
In parallel amps add up
so
4 X 12V 9AH
in serie 48V 9AH
parallel 12V 36AH

 

[dogman dan]

That price is a bit on the high side for 9 ah IMO. If your bike can run on only 9 amps of power, they'd work. I think you need at least 15 ah though.

Mabye the same place has 20 ah units? 3 12v 20 ah packs like that make a good 36v 20 ah battery for bikes.

These maybe? But I still think it's a bit high price.

http://www.ebay.com/itm/12V-15Ah-Lithium-Iron-Phosphate-LiFePO4-SEALED-Battery-w-PCM-/171143444996?pt=US_Rechargeable_Batteries&hash=item27d8f1ba04

 

[Tommy L]

That price is a bit on the high side for 9 ah IMO. If your bike can run on only 9 amps of power, they'd work. I think you need at least 15 ah though.

Mabye the same place has 20 ah units? 3 12v 20 ah packs like that make a good 36v 20 ah battery for bikes.

These maybe? But I still think it's a bit high price.

http://www.ebay.com/itm/12V-15Ah-Lithium-Iron-Phosphate-LiFePO4-SEALED-Battery-w-PCM-/171143444996?pt=US_Rechargeable_Batteries&hash=item27d8f1ba04

I agree with Dogman on the price for the amount of discharge current. And the 15ah is less than 1C continuous discharge.

I sell A123 12v 6.9ah and 9.2ah packs. They can be discharged and maintain voltage above 12v per pack at 35amps for the 6.9ah and 45amps for the 9.2ah.
and cost is higher because they are capable of doing more work. They also start cars and motorcycle, ATV, Snowmobiles....

Remember.....you get what you pay for.

http://www.rawvelocity.com

PM me, I give ES members special pricing.

Thanks
Tommy L sends.....