Wisper Battery Failure x 2

[Wisper Bikes]

There are a wide variety of LiFePo4 batteries available, as there are all other Lithium batteries the quality varies massively as does the power available, the length of time the peak power is available and the longevity of the battery itself. The price of a battery is directly related to it's quality. I can only speak from experience, we sell thousands of batteries a year and have tried most of the chemistry types available, like nearly all high quality manufacturers we have decided not to go with phosphate although now they are cheaper. Our batteries last just as long as the phosphate batteries we have tried but keep the maximum power available (for hill climbing etc) for more of a journey, are much lighter and less volume so we can pack nearly 17Ah in a 36V battery pack which drives the bike about 50% further than the equivalent battery weight and volume LiFePo4, unfortunately this does cost more. However you will find 10Ah 36V batteries are not that much more expensive than a LiFePo4 of the same power.

We are constantly experimenting with new technology, today I am off to test a new battery which currently has 2.5 x the energy density of even our best batteries (36V 40Ah) and so instead of nearly 700Wh of power we will be able to increase that to almost 1.5kWh, and these batteries are 100% bio degradable!

Regarding battery warranties, all British Electric Bicycle Association members certainly and I would imagine all decent bike suppliers will honour their commitments, if they say two years and the battery has not been mistreated the warranty will stand. If a BEBA member does not honour any of their claims there is recourse through BEBA who will help you resolve any disputes.

Best regards

David

 

[Eaglerider]

"36V 40Ah"!! Wow.

That must be good for 100 miles range.

I want one.

Thank you David for another informative post.

 

[Wisper Bikes]

Hi Eagle Rider, thanks for your comments!

Yes it is very exciting, we can stretch to 100 miles on our current battery (perfect conditions) we are expecting to break the 200 mark with this one.

The really exciting thing is this is a British firm! We are currently developing our 2013 range to take advantage of this amazing new tech, by then they are expecting to be up to 4 x energy density!

Must go, I have to be there in a couple of hours!

All the best

David

 

[Deleted member 4366]

The price of a battery is directly related to it's quality.

I think that that statement is misleading. It gives the impression that the more you pay for a battery, the better the quality of the battery, which is simply not true.

There's a lot of different factors that affect the quality of a battery and there's a lot of factors that affect the price. Most of the factors in these two groups are totally unrelated. I worked in quality assurance for many years and I learnt from the beginning that good quality often brings costs and hence prices down - as I'm sure that you have by now as well.

 

[carpetbagger]

Wow,200 miles off one charge,but realistically that would be about 170....still enough to make your knees buckle when you get off the saddle,thats if it doesn't need to be surgically removed ! .I think thats as far as you need to go on the range side now. The next step would be the same battery with a five year warranty closely followed by the same battery but half its weight. If this battery is made available for me it would be a big step for ebikes. A 36a Panasonic orBMS would do the same job...can't wait.......Hopefully when my 18a dies then something along these lines will be available.

 

[Ultra Motor]

I'm with David here. The cost for us to buy a Panasonic battery, for example is far higher than to buy an unbranded battery from the market. There are a few reasons we use a branded battery:

1. Good quality cells that last longer
2. Good electronic connectors and packing to make it safe and durable
3. Peace of mind that its safe
4. MSDS documents that make shipping much easier.

There is also the margin aspect, which I have touched on before. We have to make a margin, as do the dealer so we can pay our overheads and keep supporting bikes in the market. Look at 'David1949's post about distance support, its not as straight forward for the consumer. Whereas if he had a dealer locally to pop into it would be much less hassle. But that dealer isn't, obviously, going to work for nothing.

I think the dealer network is crucial to the development of the market and this is something BEBA strongly stands by. We can all sell batteries cheaper if we sell direct

Just our view.
Mark

 

[jerrysimon]

I wonder what the average length of ride is for most ebike users. I would guess 10-15 miles max ?

What we need is a general consumer battery to cover most users at around the £100-£150 mark that is light (2-3kg) and lasts at least 2 years/500 charge cycles. This is where the volume sales will happen and ebikes would become more popular.

There will always be a minority at the other end of the spectrum wanting something different like the above 150/200 mile battery or like myself a flat 10 mile round commute on a £60 DIY battery. There are also many DIYers happy with Lipos as well.

Development seems to be aimed at bigger and longer lasting/mile batteries. I think its time to consolidate on a battery that would meet the needs 90% of potential new ebikers.

Regards

Jerry

 

[NRG]

Agreed Jerry, I've done a few 45+ mile rides but its not something that I do on a regular basis or something I particularly enjoy! ~25 is more my range and lower cost smaller capacity battery is good enough for this.

 

[bode]

I wonder what the average length of ride is for most ebike users. I would guess 10-15 miles max ?

I use my bike only for leisure rides, and was frustrated by the range of 18-22 miles I was getting. So I went for a 20Ah LiFePO4 replacement with a range of up to 50 miles. With this I should never have to make for home just because the battery is running out.

But I do appreciate that for many others this would be over the top. We do need a range of available options, and I imagine that price, longevity, and weight would be at the top of most people's criteria list.

 

[Eaglerider]

Agreed Bode.

I tend to go for long leisure rides, and for me, range is everything, and makes the difference between a practical and useable device, and a mere toy. I have a 17 amp 'fuel tank' and can confidently go out 20 miles and back 20 miles on a charge with a good margin for extra high winds and steep hills, of which I have many.

With additional range, I would like to ride all day long. Think of all the pubs I could visit, Heh!

Of course, range would be less important if a re-charge only took 10 minutes!!

 

[carpetbagger]

Agreed Bode.

I tend to go for long leisure rides, and for me, range is everything, and makes the difference between a practical and useable device, and a mere toy. I have a 17 amp 'fuel tank' and can confidently go out 20 miles and back 20 miles on a charge with a good margin for extra high winds and steep hills, of which I have many.

With additional range, I would like to ride all day long. Think of all the pubs I could visit, Heh!

Of course, range would be less important if a re-charge only took 10 minutes!!

I think you hit the nail on the head with the last quote about a 10 minute recharge.That would kill the need for larger batteries altogether. My rides are also leisure rides, less than 20 miles now is hardly worth getting the bike out for. Most of my rides fall in the 20-45 bracket with a few 45-65 thrown in for good measure. But the more you ride,the fitter you get and subject to available time the further you want to go.
But what this has to with faulty Wisper batteries i don't Know. I think David at Wisper should have started a new thread on his future batteries...haha

 

[bazwaldo]

The main consideration for me is that my bike battery can cope easily with my 26 mile work commute on 1 charge.
That is why I spent an extra £200 on the 16ah battery instead of the 10ah version.
If the battery is able to do my work mileage including the few climbs throughout the year in all temperatures and wind conditions I am happy.
The new batteries referred to above sound fabulous and I just hope I can eventually find a replacement to fit my bike which does seem to have a fairly standard size case that fits behind the seat post.
Wisper's new battery sounds very promising, I really hope it lives up to expectations.

Barry.

 

[AndyB]

Thanks for many responses, seems experience is mixed with some saying 2 years is about it for a battery whatever the usage, and others going strong well past that. To clarify my first battery failed after 9 months, which Wisper reaplced with a recon for me (because it was out of warrantee) but this second one lasted just over 2 years, so it may be par for the course according to some posts. If that's the case then I don't think I'll pursue pedeleccing, despite being a real advocate last year, because it will work out far more expensive than motoring with me only doing 1 x 22 mile return journey a week. If batteries expire on a time basis then I think only a frequent user (3+ times a week) will see a benefit in terms of running cost.
Anyway, I am corresponding with Wisper, not that they have any obligation to replace a battery this old, that itself was a replacement for an initial failure. It maybe that the DIY solution some of you advocate is the only way to make it economically viable.
Haven't had time (or dared) take battery apart yet....
Andy

 

[Wisper Bikes]

I'm with David here. The cost for us to buy a Panasonic battery, for example is far higher than to buy an unbranded battery from the market. There are a few reasons we use a branded battery:

1. Good quality cells that last longer
2. Good electronic connectors and packing to make it safe and durable
3. Peace of mind that its safe
4. MSDS documents that make shipping much easier.

There is also the margin aspect, which I have touched on before. We have to make a margin, as do the dealer so we can pay our overheads and keep supporting bikes in the market. Look at 'David1949's post about distance support, its not as straight forward for the consumer. Whereas if he had a dealer locally to pop into it would be much less hassle. But that dealer isn't, obviously, going to work for nothing.

I think the dealer network is crucial to the development of the market and this is something BEBA strongly stands by. We can all sell batteries cheaper if we sell direct

Just our view.
Mark

Thanks Mark, service of course does have to be paid for and is in the price of anything, anyone buys. I also agree 100% with D8veh, as there are certainly more factors to price than the cost of components. I do maintain though that more expensive and higher quality components will also have a direct effect on price.

The majority of manufacturers and importers work on roughly the same margin, if they work through a dealer network they work on a reduced margin so the dealer can make a profit to enable them to look after the customer locally. This will increase the price of the bike a little however in my experience most reliable companies and end users feel the advantages of sales and service points close to the customer is worth the premium. Of course we all have the choice and some will certainly elect to buy from an importer with a web site or indeed an unbranded product directly from a manufacturer in China. Will this course be less expensive in the long run? IMO, probably not.

Best regards

David

 

[Wisper Bikes]

Wow,200 miles off one charge,but realistically that would be about 170....still enough to make your knees buckle when you get off the saddle,thats if it doesn't need to be surgically removed ! .I think thats as far as you need to go on the range side now. The next step would be the same battery with a five year warranty closely followed by the same battery but half its weight. If this battery is made available for me it would be a big step for ebikes. A 36a Panasonic orBMS would do the same job...can't wait.......Hopefully when my 18a dies then something along these lines will be available.

Hi Mick

We will not be using this new Tech to increase range on our 2013/14 bikes, we will simply be reducing the size and weight of the battery whilst retaining a 500Wh capacity, we may even reduct to 36V 10A or a 360Wh capacity, this way we believe we can get our bike weight down to under 16kg. Our target for the new bike is -16kg, 60 mile range and a very discreet sports bike like design, that said we will be continuing with our current bikes but will be offering huge range touring bikes as an option. Yesterday I learned that this amazing new chemistry will enable batteries to be delivered without any charge whatsoever, they come to life during the first charge performed by the customer. This means the batteries will have a shelf life massively better than any of the current lithium cells on offer.

All very exciting!

Best regards

David

 

[Wisper Bikes]

Hi Andy, thanks for your post, if you are not familiar with lithium batteries please do not attempt to take it apart, there are massive amounts of charge in there and opening the case can be dangerous.

Regarding your recent battery experiences, I would suggest that something is going wrong somehow. If lithium batteries are properly looked after they will last five or six years especially with the low mileage you are doing. We have customers on 6 year old bikes still using the original battery and consider lithium batteries have come on leaps and bounds since then.

The way lithium celled batteries are treated is paramount to their longevity. As I have said previously in this thread it is so important to keep the battery topped up and never leave it for any length of time without a charge. Batteries will continue to discharge even when they are not in use, especially if they are left connected to the bike. Our and most other lithium batteries have a safety cut out at or about 31.5V the reason for this is two fold. Firstly much under 31V and there simply is not enough power in the battery to make the bike run efficiently or effectively and secondly it leaves about 5V safety margin to protect the cells. If a current lithium battery falls to 24/5V it renders it completely useless and damaged to the point it probably cannot be recovered. Even at 26 to 30V the effect on the ability for the battery to hold a full charge can be greatly impaired. The new Wisper chargers start on a very low .2A trickle charge if it recognises the battery has fallen below 31.5V which helps balance cells and repair any possible damage. However as I keep banging on it is better to look after a battery well in the first place, if it has been well kept a decent lithium cell will last for many years.

Best regards

David

 

[Oxygen Bicycles]

1. Good quality cells that last longer
2. Good electronic connectors and packing to make it safe and durable
3. Peace of mind that its safe
4. MSDS documents that make shipping much easier.


Mark

Agree with Mark here that good quality cells help but not always. Very often many problems with li-ion batterries are not cell quality related and there are other parts of the battery which I would say have to be A-class i.e:

- quality of BMS. this can really mess the battery a lot
- quality of assembly, precision in soldering joints and connectors
- quality of fuses and the fuse holders (Ha you would be amazed how many of these are causing chaos in ebike batteries)

So I all I want to say is that if the Panasonic celled battery is assembled by bad assembler it will cause a lot more trouble then the pack with unbranded chinese cells but assembled by proffesionals. Being in the ebike market I personally tested many different suppliers before selecting the right partner. Many make statements that they use Panasonic cell so they have the best quality and yes they do but along with Panasonic cell they use the most basic bms, cheapest wiring, their fuse holders can melt at 15A and at the end of the day the battery is just as bad as most cheap unbranded packs.

 

[piotrmacheta]

We have a battery manufacturer on our business park (Culham Science Centre) and only yesterday I found out that they will be making some new Lithium Sulphur batteries that have 4x the capacity of current Li ones. Apparently available in 2013. I can't wait.

I've done over 3000 miles on my old (2008) ezee battery (20 miles per day commuting and the rest) and it's just starting to dip a bit in the cold weather but I'm happy with the service I've had from it - much cheaper then using my 3.0L V6 petrol car!

Looking after the batteries and not discharging them fully all the time is very important for long life as has been said already. I found a little gadget that may also help. I use a Lithimon 9012 primerily as an alarm to warn me when my battery is close to empty but it also has built in capacitors and is marketed as helping the battery maintain it's performance during discharge. In fact it does seem to work as with it, on a cold morning like today, with a part discharged battery, I have found that the batt voltage under peak load is 2 or 3V higher than without it so my battery can go further.

Electronics for Radio Control Modellers

One thing I'm never sure about is how effective the low voltage cut out systems. Do they work off the BMS and cut the whole pack when one cell goes low or do they work of the total voltage of the pack? If the latter then it must be possible for a single cell to droop to unsafe levels and therefore never running the pack down to the trip is bound to increase the battery lifespan.

 

[piotrmacheta]

OOps, just seen an earlier post ref Wisper and Oxis - these are the people here on site - I'm so lucky! I enquired last year ref buying a battery from them but was told they don't make any with high enough capacity as they only made them for satellites. Things have clearly changed.
I found out they were there a couple of years ago due to an emergency call-out - making Li batteries sure is dangerous!

 

[Wisper Bikes]

Hi Piotrmacheta

I was there only yesterday, we have been working with Oxis for about 18 months and will be using their batteries in our bikes in the not too distant future. They are not cheap though!!

What a great place to work!

All the best

David