lead acid battery help please

fatts

Pedelecer
Dec 29, 2009
244
0
west wales
Hi all,

Not being that well up on batteries I am unsure of running our tricycle on 3x12v car batts. to get 36 to suppliment the bike battery to give my partner further range. I do not have a problem conecting them up putting fuse inline etc. It is will they hold the power (dependant on amperage) a I have been told they need to be special batteries by some and no prob by others so I am rather confused.
The motor being powred is a 250w,
I hope someone can help
many thanks
fatts
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
Sealed lead acid or gel type batteries should be okay. What sort of battery is the trike using at the moment?
I've been looking at some on ebay around 18-22ah which will set you back around £70-£80 for three of the cheaper one's.
 

fatts

Pedelecer
Dec 29, 2009
244
0
west wales
Hi and thank you at present its using 10 or 15 amp batts its a powabyke with a higgs conversion to turn it into a tricycle.
 

NRG

Esteemed Pedelecer
Oct 6, 2009
2,592
10
You'll need Deep discharge / cycle batteries for an E-Bike application, any old cheap SLA won't do.

IE: vbat.co.uk - Deep Cycle Sealed Lead Acid Batteries

Aim for more Ah than you think you require, A) because of the Peukert effect (Google it) which will reduce effective Ah by about 1.3 so 10Ah becomes 7.7Ah and B) SLA's don't like deep cycle discharges... so to keep Depth of Discharge (DOD) as low as possible use more AH than is needed on paper.
 

rog_london

Esteemed Pedelecer
Jan 3, 2009
764
2
Harrow, Middlesex
I wasn't going to get involved with this one - however:

Generally if weight isn't a problem but you want a decent capacity use car batteries. They're cheaper than anything else watt for watt. As it's a trike and is hopefully unlikely to be overturned it's a fair choice.

Some points about lead acid batteries I've mentioned before but they'll bear repeating:

(1) Aim for double the capacity you really think you need. If you only discharge half way (max) you might well get 600+ recharges. Even 'deep cycle' batteries don't last long if you habitually - er - deep cycle them, i.e. use all of the available capacity, and you'll be paying a premium for something which might not be much help.

(2) Recharge as soon as possible after ANY discharge. Even a small discharge left for a few hours can make a difference. They like to be kept fully charged whenever possible.

(3) Shelf life of a car battery which is looked after (see above!) can be 5 to 10 years, with more than half of the initial capacity being available after that time. The same applies to most larger SLAs. That's MUCH better than the lightweight Li-ion (etc.) technology we normally use, and shouldn't be discounted.

(4) Most SLAs below the 17AH size are not up to the heavy short-term discharge currents involved in driving a vehicle. Make sure if you buy SLAs that they have screw terminals or clamp posts like a car battery, but NOT spade connectors.

Rog.
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex

Providing there not run completely down which is impossible with the dod cutout, I can't see why not. Funny thing is, looking at standard sla prices they appear to be more expensive than deep cycle one's? These, being 17ah and having bolt connection's should be ideal in my mind. Just charge after use and don't allow them to run down too far as Rog say's.
I think sla's have advantages over Lithium, price and availability being the two biggest. As far as green issue's are concerned, lead is a re-cycleable material.
 

GT3

Pedelecer
Aug 12, 2009
100
8
Cab anyone help with my SLA conundrum?

Originally purchased four cheap Chinese Potevio 12V 14Ah batteries from Ebay. £88 delivered.



With a 1000W 48V motor, these gave 25 miles range. Using them for a 16 mile journey, they started to weaken after about 120 charges. Symptoms were lack of zip, but no cutting out.

Replaced with Lucas 12V 12Ah ("but really 15Ah (new description legislation)") £100 collected.



No real 'zip' when fully charged and the bike is cutting out (assumed controller) after 15 miles?

I spent more on ostensibly better quality batteries and am worse off? What's the difference?
 

Fecn

Esteemed Pedelecer
Sep 28, 2008
491
2
Warlingham, Surrey
Originally purchased four cheap Chinese Potevio 12V 14Ah batteries from Ebay. £88 delivered.

Replaced with Lucas 12V 12Ah ("but really 15Ah (new description legislation)") £100 collected.

I spent more on ostensibly better quality batteries and am worse off? What's the difference?
I make it twelve quid :) ... sorry.. couldn't resist.

Other than that.. The Lucas batteries may not actually be designed for Traction use, whatever the seller's description says - They have spade terminals on the top rather than bolt-on terminals, which is generally an indication that they're more suited for standby-use (fire alarms etc) than for higher current e-bike use.
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
Cab anyone help with my SLA conundrum?

Originally purchased four cheap Chinese Potevio 12V 14Ah batteries from Ebay. £88 delivered.



With a 1000W 48V motor, these gave 25 miles range. Using them for a 16 mile journey, they started to weaken after about 120 charges. Symptoms were lack of zip, but no cutting out.

Replaced with Lucas 12V 12Ah ("but really 15Ah (new description legislation)") £100 collected.

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?VISuperSize&item=
300402393446

No real 'zip' when fully charged and the bike is cutting out (assumed controller) after 15 miles?

I spent more on ostensibly better quality batteries and am worse off? What's the difference?


You may find an improvement after several cycle's but 1000w is heavy going and as already said the lucas batteries may not be designed for this kind of heavy use. Numax seem to be the only reasonably priced sla's on ebay at the moment that are deep cycle capable although that doesn't mean they can handle the high continuous discharge rate required by your ebike.
 

eddieo

Banned
Jul 7, 2008
5,070
6
This was posted by wisper over on "clinic" threads..

"As far as tech is concerned we will be carrying on along the lithium rout for the time being although we are looking at Bi Polar lead acid batteries as a less expensive option. The lead acid cells will be fitted into our existing boxes and being 36V will work perfectly"

So....... maybe not the end of SLA's yet:confused:
 

Wisper Bikes

Trade Member
Apr 11, 2007
6,314
2,279
69
Sevenoaks Kent
Lead Acid

Certainly not Eddie

There is a lot of research currently under way and we are exploring the possibility of using Bipolar lead acid batteries as a low cost option on our bikes for people who don't need such a large range.

Bipolar Lead Acid batteries are clean efficient, can be charged/discharged 200 times before the loose power and are 97% recyclable in the UK.

All the best

David
 

eddieo

Banned
Jul 7, 2008
5,070
6
Certainly not Eddie

There is a lot of research currently under way and we are exploring the possibility of using Bipolar lead acid batteries as a low cost option on our bikes for people who don't need such a large range.

Bipolar Lead Acid batteries are clean efficient, can be charged/discharged 200 times before the loose power and are 97% recyclable in the UK.

All the best

David
are they prone to extreme mood swings as the name suggests?:D
 

GT3

Pedelecer
Aug 12, 2009
100
8
You may find an improvement after several cycle's but 1000w is heavy going and as already said the lucas batteries may not be designed for this kind of heavy use. Numax seem to be the only reasonably priced sla's on ebay at the moment that are deep cycle capable although that doesn't mean they can handle the high continuous discharge rate required by your ebike.

Thanks for the replies.

The ebay seller sold Numax and Lucas, I bought the best name. Never mind. From a bit of research last night, I gather the term 'deep cycle' is applied to batteries being 20% discharged, which does not help us.

Can anyone recommend any other sources SLA's suitable for our use?