Hello, new project on the go, battery help needed please!!!

dshaw647

Finding my (electric) wheels
Oct 24, 2014
6
0
43
cHi all, have just been on hols near cromer (gt yarmouth way) and the frendly chap in the local ebike shop recommend this site for good advice..so here go's,
Just building my own front drive 36v 500watt ebike. I have all built the bike/conversion but batteries seem to be an issue (bet this aint the first time youve heard that old chestnut!!!) I brought a lithium 36v 10a underseat battery off ebay for £190 but there was no connectors or way of mounting it to my bike so I sent it back. so my question is, are there any more universal type lithium batteries anyone can recommend? Also if I just go to my local battery suplier and buy something like 3x 12v 10ah sla batteries are there any other things I need to tell them (am aware there heavier and not as good as lithium but for my first build and till I know my motor/speed controller work fine!) also were can I get a good balance 36v charger? as I have so far only seen one with crockadile type connectors and its in calaforna! (£30) And would I be best to add a fuse? Added pics of my speed controller and current battery connector.
Any help would be greatly appreciated!!!
Regards, David.
 

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trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
bottle battery to go on the down tube.

Like this:

 

dshaw647

Finding my (electric) wheels
Oct 24, 2014
6
0
43
cHi all, have just been on hols near cromer (gt yarmouth way) and the frendly chap in the local ebike shop recommend this site for good advice..so here go's,
Just building my own front drive 36v 500watt ebike. I have all built the bike/conversion but batteries seem to be an issue (bet this aint the first time youve heard that old chestnut!!!) I brought a lithium 36v 10a underseat battery off ebay for £190 but there was no connectors or way of mounting it to my bike so I sent it back. so my question is, are there any more universal type lithium batteries anyone can recommend? Also if I just go to my local battery suplier and buy something like 3x 12v 10ah sla batteries are there any other things I need to tell them (am aware there heavier and not as good as lithium but for my first build and till I know my motor/speed controller work fine!) also were can I get a good balance 36v charger? as I have so far only seen one with crockadile type connectors and its in calaforna! (£30) And would I be best to add a fuse? Added pics of my speed controller and current battery connector.
Any help would be greatly appreciated!!!
Regards, David.
bottle battery to go on the down tube.

Like this:

Thanks seen a few of these, do they have wires to connect to my speed controller though? as don't mind making a different plug but the last one I brought didn't and was sealed so didn't want to butcher a £190 battery that much!!!
 

dshaw647

Finding my (electric) wheels
Oct 24, 2014
6
0
43
Thanks seen a few of these, do they have wires to connect to my speed controller though? as don't mind making a different plug but the last one I brought didn't and was sealed so didn't want to butcher a £190 battery that much!!!
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
this sort of batteries comes with lead, charger and fuse. See the plastic case on the seat post? the controller goes there. The controller box does not have to go up that high, probably can be tucked in between the battery and the seat post. If you want to keep the controller in a triangle bag, then extending the battery lead is easy with two core silicon wires. The lead from the battery is about 50cm long.
 
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dshaw647

Finding my (electric) wheels
Oct 24, 2014
6
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43
this sort of batteries comes with lead, charger and fuse. See the plastic case on the seat post? the controller goes there. The controller box does not have to go up that high, probably can be tucked in between the battery and the seat post. If you want to keep the controller in a triangle bag, then extending the battery lead is easy with two core silicon wires. The lead from the battery is about 50cm long.
Thanx trex,
Can I where you got yours from and how much?
Was thinking of putting the speed controller in one of my side panniers to protect it from the elements, was also thinking this may also be more "discreet" if you get my meaning!
;-)
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
I don't have one of those. Woosh sell the 36V 15AH battery + charger for £315.
http://wooshbikes.co.uk/?batteries#batkit
There are other vendors on ebay too:
http://www.ebay.co.uk/itm/New-2014-Model-36v-11ah-water-bottle-mount-Lithium-ion-electric-bike-battery-/311003291968
You have a 500W motor, you'll need a battery capable of high discharge rate to get the best out of the motor, that means a 15AH battery can deliver more continuous current than a 10AH battery. The maximum you can draw in Amps is 2C with Samsung and NCR cells, 1.5C for no-name cells.
 
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OldFart

Pedelecer
Sep 30, 2014
91
8
58
Middle bit of the UK.
DON'T goto SLA's.... I am new here and bought a "Thing" see my other threads.
It came with 3 x 12v 10Ah SLA's. I weighed them today. 13.3kg.

I have a pair or 18v 4Ah lipo batteries and they weigh just under 1kg.
Seems the 4Ah lipo may actually give as much power as the 10Ah SLA's?

Even adding another 2 pairs. That will give me 12Ah and only come in at 3kg.
A quarter the weight of the SLA's.

One thing i spotted in your picture the wire going into the wheel needs to be facing downwards. Seen that mentioned on here several times.

The way you have it in the picture, water will run down it into the motor. It needs to loop downwards and then come back up. Water will run down and drip off the bottom then.
 
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dshaw647

Finding my (electric) wheels
Oct 24, 2014
6
0
43
I don't have one of those. Woosh sell the 36V 15AH battery + charger for £315.
http://wooshbikes.co.uk/?batteries#batkit
There are other vendors on ebay too:
http://www.ebay.co.uk/itm/New-2014-Model-36v-11ah-water-bottle-mount-Lithium-ion-electric-bike-battery-/311003291968
You have a 500W motor, you'll need a battery capable of high discharge rate to get the best out of the motor, that means a 15AH battery can deliver more continuous current than a 10AH battery. The maximum you can draw in Amps is 2C with Samsung and NCR cells, 1.5C for no-name cells.
Thanks again,
Have found a few local agents (thanks also to this webisite) so gonna ring around when they open today!
 

dshaw647

Finding my (electric) wheels
Oct 24, 2014
6
0
43
DON'T goto SLA's.... I am new here and bought a "Thing" see my other threads.
It came with 3 x 12v 10Ah SLA's. I weighed them today. 13.3kg.

I have a pair or 18v 4Ah lipo batteries and they weigh just under 1kg.
Seems the 4Ah lipo may actually give as much power as the 10Ah SLA's?

Even adding another 2 pairs. That will give me 12Ah and only come in at 3kg.
A quarter the weight of the SLA's.

One thing i spotted in your picture the wire going into the wheel needs to be facing downwards. Seen that mentioned on here several times.

The way you have it in the picture, water will run down it into the motor. It needs to loop downwards and then come back up. Water will run down and drip off the bottom then.
Thanks,
didn't even think about the cable through the wheel! although not totally wired it up yet till I sort a battery, but thats great advice when I do!
as I just said to Trex, think I'm gonna try somewere local now for a lithium battery so I can take my bike in and try as don't fancy spending the best part of £300 on a battery if the kit I've brought is rubbish! also the last lithium battery I bought off ebay, the company wasn't very helpful, had no fittings and didn't want to refund when I sent back (had to open dispute!)
cheers again for advice :)