Just plain NiMh battery packs

I have searched the forum to see if this has been asked before, but I cant find it. Heres my query:

 

Can you buy just plain NiMh battery packs in either shrink-wrap or plain non-specific battery cases?

 

The reason I ask is that I have an ordinary MTB with a 24v hub kit. The Li-ion battery that came supplied with the kit was (in my opinion) not performing correctly (now returned to supplier for testing).

 

The battery was only connected to the controller with two wires with bullet connectors and could be carried in a rack bag, pannier or fixed to the frame with the clamp supplied. So it seems that any 24v pack whether SLA, Li-ion, NiMh etc could be used for power. Unlike ready made e-bikes with "cartridge type" batteries which are designed to fit somewhere in the frame with electrical connections to slide into, hub kits like mine can use virtually any pack with just a minor adaptation to the electrical connections to the controller. But I cant find just plain packs!

 

I followed 'Allotmenteer' and bought the Windsor 24v NiMh pack from Powabyke. I had to make a slight adaptation to the connections and the pack performs faultlessly. I am not quibbling about its cost (£99), but I wondered if part of this cost was for its casing, warning level lights, on/off key and new lock cylinder (which real Powabyke users would need).

 

In a nutshell: Is there a market for just plain NiMh battery packs (24 + 36v) for those just want to carry/use them in rack bags, panniers etc - and if so, is there a supplier?

 

Richard (aways wanting to save a penny where possible:rolleyes: )

There are suppliers of induvidual cells and I have seen links on this forum to suppliers of made up packs, though not necessarily designed for bike use. However none of these come close to the excellent value of the £99 Powacycle pack which is less than £5 per cell. This is even more true now that many suppliers have increased prices in response to the current world nickel shortage.

However none of these come close to the excellent value of the £99 Powacycle pack which is less than £5 per cell. This is even more true now that many suppliers have increased prices in response to the current world nickel shortage.

 

 

Whoops!, sorry I asked now. Perhaps this thread should be deleted before Powabyke puts its prices up !

 

Seriously though, I had only wondered about this as I had read (cant find it now:( ) a message from Andrewelectricbiker? where he had sent an old battery pack which I assumed was the 'cartridge type' to be refurbished with new cells to a company called 'Cell Pack Solutions'. I dont think he said how much this cost but I assume that it must have been less than a direct manufacturers replacement or he wouldnt have done it.

 

Still, as I said before, I'm not quibbling about the price I paid - it performs very well and I'm very happy with it at £99 (its just that I'm a tight ol' git)

 

Richard.

There is this thread Richard, where member pgbw had been quoted £280 for re-celling an Ezee 36v battery by two companies.

 

Hopefully the Nickel crisis will be resolved and prices should drop to a more realistic level, however to their credit Powacycle have maintained the price constant while some other suppliers have virtually doubled theirs.

 

It's interesting that you have had problems with a Li-ion battery, a number of other forum members have expressed dissatisfaction with Li-ion types. I came to the conclusion a while ago that NiMh was more suitable in this application, a view which is continually being reinforced by the experiences of others.

Edited July 7, 200718 yr by Ian

My ears are burning.. This is why I was moaning about having the battery FAQ section where we could share battery info.

 

Eddie at cellpack solutions makes up ebike batteries. He also refurbs cassette type packs. I am not sure whether they can source NiMh at the best price though. Try Ebikes.ca store whose packs are competitive due to favourable rates at the moment. Try the other forums below who are more geared to homegrown kits rather than uk pedelec retail bikes.

Andrew

The big problem is that if you want to throttle commute a fair distance then the average ebike pack only gives max 10 months worth of 2 a day charges.

 

How is that for a contentious claim?

The big problem is that if you want to throttle commute a fair distance then the average ebike pack only gives max 10 months worth of 2 a day charges.

 

How is that for a contentious claim?

 

I don't think that's contentious Andrew, it's more or less in line with the 500 charge/discharge cycle life that most suppliers claim.

 

More moderate users can expect rather longer lives from NiMh though, my oldest (>1 year) and newest (3 months) batteries have identical performance and range. That doesn't necessarily apply to lithium types though.

When I first published the availability of the Powacycle battery on my Twist site, the cost was only two thirds that of Cellpack solutions recelling service, and as Ian has said, by far the cheapest source 24 volt for cellpacks or batteries.

 

However, Cellpack weren't up to recelling the Giant batteries, finding they couldn't successfully do it, goodness knows why not, it's easy enough if they'd followed what I said. Many owners have since done it ok.

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My ears are burning.. This is why I was moaning about having the battery FAQ section where we could share battery info.

 

Andrew and all,

 

I've modified the Battery FAQ forum permission to allow posting of new threads so you can now start and reply to specific battery topics. We'll see how it goes for a while.

Re: NiMh battery life, much depends on the battery and charger design and quality.

 

For the best part of four years I used a twist for everything, utility cycling, trailer towing etc, and in daily use often seven days a week.

 

Coming up to four years old I recelled one battery just to return the range to a full distance, it otherwise still performing ok. The second four year old battery not recelled I've passed on to Alan Terrill who is using it as a "get-home" back up and it's still working ok.

 

In small part this long life is due to the quality Panasonic cells, but the most important factor was the excellent Metco charger with it's regularly used "refresh" discharge facility. The Metco charger I bought when the Panasonic one Giant supplied failed very early, it being Giant's temporary stopgap charger.

 

The biggest failing of the NiMh chargers supplied with many e-bikes is the lack of a discharge facility, this being essential for a long NiMh life.

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When I first published the availability of the Powacycle battery on my Twist site, the cost was only two thirds that of Cellpack solutions recelling service, and as Ian has said, by far the cheapest source 24 volt for cellpacks or batteries.

 

However, Cellpack weren't up to recelling the Giant batteries, finding they couldn't successfully do it, goodness knows why not, it's easy enough if they'd followed what I said. Many owners have since done it ok.

.

 

They might be turning in a different direction now. Last year they re celled my 36v NiMh for around £4 a cell. I want more capacity now because I am running on lazy throttle over hills to work and back:D . Powacycle don`t seem to offer a 36v NiMh replacement pack.. which would suit me fine.

The biggest failing of the NiMh chargers supplied with many e-bikes is the lack of a discharge facility, this being essential for a long NiMh life.

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Hi Flecc,

 

As I have only had the Windsor NiMh pack and charger for a week I would obviously like to keep the battery in its best condition. I understand what you are all saying about fully discharging the battery.

 

I use the bike purely for leisure (retired). I often use it just for 4-5 miles a day just to get out of the house. I think I am getting about 15 miles of good power from the battery before it feels like it is not giving the same assistance (throttle 'low' light comes on when throttled hard). I am pretty sure I have just had 15.8 miles since my last charge and the battery now reads 24.2v on my meter.

 

As there is probably not much assistance left in it - should I recharge it now, I have not got a "refresh" facility so would I be better off "hooking up" the back wheel off the ground and taping up the trottle until battery is empty.

The only other option would be to continue to use the bike until battery was exhausted, but that would probably be when I was a distance from home and I would end up pushing it back....then I would be exhausted. (I must try and remember to put a postit note or something on the battery with a note of mileage at last charge) - I would try and use the bike until it was totally flat but my wife would not be too chuffed with my "Can you come and pick me up please?"

 

Richard

Hi Richard. That 15 miles on the Windsor is quite close to a full discharge so is the next best thing, and I sometimes accept similar on my eZee NiMh battery.

 

That's the important thing, if not a full discharge, close to it. The worst thing is to charge every few miles with light use and never fully discharge, a sure way to short life.

 

Holding the motor wheel off the ground and running it won't help, the consumption is vanishingly small if the motor isn't under load. I once turned my Torq upside down and set the throttle to full on with a half charged battery. Eight hours later it was still running just as fast, so I think you might need to go on holiday to be sure of running it down that way!

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Holding the motor wheel off the ground and running it won't help, the consumption is vanishingly small if the motor isn't under load. I once turned my Torq upside down and set the throttle to full on with a half charged battery. Eight hours later it was still running just as fast, so I think you might need to go on holiday to be sure of running it down that way!

.

 

You could just ride up and down a local hill a few times to get the last few out

Andrew

You could just ride up and down a local hill a few times to get the last few out

Andrew

 

That's what I do Andrew, and am lucky (?) enough to live up a 1 in 7, but on the day it question it was bucketing down and the hill was doing it's Niagara Falls impression again.

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hi considering the high cost of replacement batteries and sometimes the short life,is it not time that 50 cycles had more faith in there products, not just this supplier but others as well and offer a better guaratee.Ezee in the States give a 12 month guarantee on batteries we get 6, Sparta and others now offer a 2 yr guarantee on there batteries.

Batteries are like people, give them a light workload and they live a long and healthy life. Work them into the ground and R.I.P. Always buy batteries larger than you think you need. Oh! and NiMh do not need to be drained, infact it shortens their useful life.

Urstu, that guarantee situation has been the same fior years on many products. For example many Sony products in the USA have much longer warranties than here in the UK. It's a case of what they can get away with, and consumer power in the USA is stronger.

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Oh! and NiMh do not need to be drained, infact it shortens their useful life.

 

Very bad advice FatPete. NiMh still have a residual of the memory effect that plagued NiCads, and a cell that is never properly discharged to just over 1 volt has it's life shortened.

 

I think you may be mixed up between completely emptying the cells, which certainly damages them, and emptying them on the bike or discharging them through a properly designed discharging circuit that drains them to just over 1 volt. Either of the latter intermittently is essential for long life, and experience with our bike batteries shows that very clearly. You won't find a battery authority or manufacturer anywhere who supports never discharging them.

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I bow my head to the greater good, Everyday is a school day. regards FatPete:eek:

Everyday a School Day!

 

I bow my head to the greater good, Everyday is a school day. regards FatPete:eek:

Inm praise of Flecc.

I was never so overjoyed until I left school (or so I thought I had until post school qualifications reared their beautiful head - beautiful as it turned out).

Knowledge is beautiful and I beg you to enrich my world Flecc.

My LITHIUM Manganese batteries are already showing signs of serious decline - on which I should like your comments. I know the basics - "down by 20% in the first year - don't deeply discharge", etc:

 

1. Lithium-ion 37V 10Ah - bought July 2006 - 28 miles range on flatish terrain- falling to 25 miles (in Torq) and now reached 18 miles (in Sprint 7) moderate hilly terrain as below. Never abused: deeply discharged for 3 conditioning cycles. Used mainly for distance cycling of 15 - 20 miles: taken off the bike "when the yellow light remains on whilst on a level road". Always recharged after a journey no matter how short.

 

2. Lithium-ion 37V 10 Ah - bought May 2007 - best range 22 miles - moderate hilly terrain (ie up to 500 meters/7%) (in Sprint 7). Never abused (by me): deeply dischatged 3 conditioning cycles. Used mainly for distance cycling 15 miles +. Best range 18 miles. Taken off the bike and recharged "when the yellow light remains on whilst on a level road". Always recharged after a journey however short.

 

3. Lithium-ion 37V 10Ah - bought June 2007 - same as above para 2.

 

All three batteries seem to be performing in much the same fashion BUT not like the first did in the Torq.

 

I've noticed that there are many batteries that look much the same and are sited on the bike behind the seat tube. Might they be compatible with the Ezee range of cycles with some simple modification? e.g. like an adaptor plug (you can probably tell I've never seen the battery off a Wisper bike - so forgive me if it's a daft question).

 

One lives in hope that NiMH come back soon as they appear to suit my cycling philosophy much better than the "Faint-hearted Lithium"

Peter

The advice I give is generic for Li-ion Peter, but is also dependent on individual battery quality. I've made mention on my website about inconsistencies in this, and have suffered the same sort of thing you have.

 

Two batteries bought with the Torq, close serial numbers, but one definitely inferior to the other eventually becoming unusable in cold winter weather at nearly 6 months old due to cutting out. The other one eventually followed this cutting out, but not so badly and is still usable in most circumstances at a year old. The third battery replacing the first one has been better from the outset, from which I conclude that the Phylion Company are learning and getting better gradually.

 

I can't quote ranges as you can, since most of my runs are shorter, but the fact that you are quoting those longer ranges shows that you have used those distances which increase aging.

 

Howver, I think that product inconsistency is the biggest problem, and like you, for me it's an NiMh future until something better comes along. That could be higher capacity Li-ions which would do the trick, or a better technology.

 

There's no reason why someone elses battery internals cant be used if they fit in the case, and the Wisper ones could be a candidate. I don't think there'd be much point though, since a wisper 905e user has already had the same cutout problem and there are very few manufacturers of these batteries anyway. The innards of another could well be from the same stock.

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Further to my reply Peter, a healthy Li-ion battery should lose no charge at all while standing. The voltage after charge will settle over many hours as the battery cools, but once settled should remain the same, even for many months.

 

The inferior one of my batteries does lose charge as indicated by a continual slight voltage loss, so it's clearly not healthy. It's likely that a cell is responsible, but it could also just be a failing in the individual cell control circuit that each cell has. Yet another inconsistency that upsets life predictions, and it might be interesting for you to check yours for charge maintenance.

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NiMH suits my usage - I regularly make long trips to full discharge.

 

You say a discharger is essential for long NiMH life flecc:

How much difference do you calculate the discharger makes from running till empty between most recharges? How much less capacity decrease per annum would you say?

Is it possible or advisable, then, to get a charger with refresh discharge built in for use with ezee batteries do you know, flecc? The Twist NiMH replacement battery charger you found can't be used for that purpose? My ezee NiMH charger seems very fast, about 2h 45min full charge: its rated as 2.6A output, is that normal or too fast for long battery life? Sorry for all the questions & apologies if you've answered this elsewhere .

 

Stuart.

I have no estimate of how much longer life discharging gives Stuart and have never seen any tested evidence on that. I base what I say on observations that others get around two to three years life on NiMh on many bikes using a mix of chargers which frequently have no discharger, or it's function isn't used by owners.

 

By contrast, Twist series batteries used with fairly regular use of the Refresh (discharge) function seem to last to four years and even beyond, true of my own two batteries too, one given away and still in use at nearly four and a half years. Not very scientific, but it fits with expert advice that NiMh should first be discharged nearly down to 1 volt per cell once every few charges, so what evidence I have indicates this is good advice to give, and it obviously does no harm.

 

Speed of charge does affect life, but I have no measure by how much. My own experience with very fast chargers (1 hour) on smaller cells is that it quite seriously reduces life, this being related to the way NiMh also cannot discharge beyond a certain rate, unlike NiCad.

 

Your charger is like mine in that time, but that's not too high a speed for cells designed for high discharge. It would be too fast for regular consumer D cells, but I would ideally prefer more like 4 hours nonetheless.

 

With discharging, there's a balance to be struck though. NiMh batteries have been quite cheap, while the Giant Twist charger currently costs at least £120, from some dealers £140. That's over 1.4 times the price of a Powacycle battery with the same number of cells, but of larger capacity.

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