eZee / Phylion Li+ battery

[WaiWonChing]

Once a year we visit our distributor for dialogue and understanding of the market, and also to resolved any outstanding problems that there maybe. Ken Ching and myself visited 50cycles in Sept 2007 for 3 working days, it has not been brought to our attention that we have a serious and urgent problem regarding the Phylion Li+ battery that we have supplied.

During the visit we also inspected the returned defective components, and for the year 2007 up to then there was about 18 units of Li+ batteries, out of which I confirmed 7 units was out of order with less than 28 volts, generally it means at least one cell must be defective. Others have 30V and above and I managed to charged a few and put them on the discharge equipment @0.5C ( 5amps ) and they were still more than 80% DOD. The others I simply did not have the time because it takes 6 hrs to make a full charge. Nonetheless we have given replacement under warranty.

I was very taken and surprised at the level of hostility and aggressiveness responding to what I wrote about the first leg of my silk route ride from Shanghai to Wuhan in the pedelec forum. Only then I became aware of the real problem existing, and obviously as I know it now, there is a very high level of misunderstanding as to the specifics and complexity of this problem. I have to admit that I have given very little time to reading the forum, as I had the wrong impression that manufacturers should not participate.

Up till then I was aware that there were complains regarding the power being cut off when climbing hills. I took it as a case of overload, we have in the past conducted severe tests on the overload situation until the tyres smokes. On this trip going over the mountain ranges for several days, I was also trying recreated situations that cause such a power cut off and nothing happened, so I wrote I did not understand why there was this problem UNLESS it is rather a case of a weak battery with low voltage protection coming in cutting off if it dips below 31.5V instead of an overload situation.

I would also like to explain the situation for both the NiMH and Li+ battery we’ve been supplying. In 2001 we started with VRLA 36V , and switched to NiMH 36V in 2003, and in Mar of 2006 we introduced and launched Phylion Li+ battery after 3 months of testing. We did it very slowly to first get market response and checked out product performance. By 2007 it has became the battery of choice, and basically all distributors opted for Li+ battery in their order. Which ever battery it is, it did not make a difference to our margin, in fact we made less with the Li+ in percentage terms, but on the other hand Phylion does give us strong support with delivery and service. Whereas we have almost no recourse what-so-ever with the NiMH battery suppliers as it was not possible to get the faulty battery returned to their factory.

Phylion is a subsidiary of Lenovo, and has strong endorsement from the China Ministry of Science and Technology, and it is in an industries list that China would like to get on par with the best in the world. As with such new technologies, there are obviously lessons to be learned from laboratory to pilot production to commercial production to large scale commercial production. We would not touch any of the other numbers of Li+ batteries suppliers in China because they do not have the people, nor the capital nor other resources that Phylion has. We have also tested LG Chem Li polymer and Valence LiFePO4 battery. These have failed quickly and were costly as well, somehow the onus for price and experimentation rested on us.

The life span of the product is a crucial factor, but it is a factor that is probably not so easy to control, especially in our bike that draws very high amps or power compared to the Panasonic system for example. eZee’s QC relies on the parameters that we can control.

Together with Phylion we will investigate very thoroughly the problem and cause of the problem and re-define what the Phylion Li+ battery would be capable of. In the meantime, we give the assurance that we will make replacement for all the customers in 2007 who has encountered problems with it.

Meanwhile NiMH battery is indeed available from us and we will include a NiMH charger at no extra cost for those who wish to switch over from Li+.


W W Ching
Chief eZee Operator

 

[flecc]

Thank you for your courteous reply and explanation Mr Ching. I'm relieved that you will be further investigating the problem that we've been experiencing, since as I believe you now understand, it is a very real problem, the batteries simply not able to discharge to the stated specifications for very long.

In my own case, this has been three batteries, two from the early days of July 2006, and an exchange one from January 2007. After it had been run in and at only one week old, the last one cut out on a sustained one mile long gentle climb. The characteristics have always been the same on this particular hill. The battery starts by performing well and with me and the bike sharing the effort 50/50 at about 15 mph on a Torq, but gradually the battery lessens it's contribution, so after a while I'm left doing most of the work and the speed down to about 12 mph until the cutout happens.

Within six months the cut-out problem is so severe that the battery becomes unusable. Of my three Li-ions, one was returned for the exchange, one I converted to NiMh, and the third is unusable now.

I have two NiMh chargers already, but those who wish to convert will doubtless be pleased with your generous offer to supply a free charger.
.

 

[ITSPETEINIT]

Li-ion Batteries swap

I think Mr. Ching certainly means that he will swap NiMH batteries for Lithium batteries that have cut out on hills.
Will he also swap those Lithiums which have defaulted out of warranty in the number of recharge cycles that were indicated (500) when the Lithiums were 'promoted'?
The steep rise in the demand for Lithiums as the battery of choice was, in some cases, mine in particular, due to the promotional encouragement of the distributor in the UK: they were stated to be 'at the cutting edge of technology, lighter and had greater range than NiMH even though they were £100 more expensive than NiMH.
How does he propose to test these cases that are brought to his notice?
Is he going to rely on 50Cycles to make the decision on a customer-by-customer basis?
I am concerned because I was 'bullied off' by 50Cycles on a legitimate claim I had on a cycle and they were not in the 'mood' to honour Mr. Chings promise to replace a Lithium battery after it defaulted having completed only 80 miles although it was out of guarantee having been 'laid up' for the winter of 2006/2007 (November to Mid- march). "We don't take instructions from Mr. Ching" is how they put it.
I regret my complaints will rattle on because I was not satisfied. Did they think I would 'lie down'?
Peter

 

[HarryB]

Yes thank you for your detailed response. In my opinion manufacturers are welcome to join the forum and enter any discussion provided the forum is not used for advertising your products (sometimes a difficult balance). The advantage to joining is while you will get negative comments about your product (which are always useful) you will also get positive comments and I am sorry you think we have been hostile.

My experience is similar to Fleccs. I bought a new Li-ion powered Torq in July and the battery failed to charge and was returned for a replacement in February 2007. The second battery seemed pretty weak and when the whole bike was returned for a cutting out problem, the battery was tested and found to be only 8.5Ah, down 15% in under 2 months. The cutting out continued to get worse and I nursed it until November 2007. The battery was never deep discharged (except for conditioning) and charged routinely after 10 miles so fairly easy conditions. I calculated this battery did no more than 130 cycles but the performance was very poor from 100 cycles onward. I have under duress bought another Li-ion battery and this is performing better than the previous battery but due to my previous experience I don't have much hope of it lasting 2 years or 300 charge cycles minimum.

In order to re-gain confidence in these batteries I think you will have to improve the guarantee from 6 months to a minimum of a year or preferably 2 years (80% depth of discharge) to match the Panasonic battery you are competing with for sales. Until that happens I will be moving over to NiMH batteries and so thank you for the offer of a free charger.

 

[WaiWonChing]

I think Mr. Ching certainly means that he will swap NiMH batteries for Lithium batteries that have cut out on hills.
Will he also swap those Lithiums which have defaulted out of warranty in the number of recharge cycles that were indicated (500) when the Lithiums were 'promoted'?
The steep rise in the demand for Lithiums as the battery of choice was, in some cases, mine in particular, due to the promotional encouragement of the distributor in the UK: they were stated to be 'at the cutting edge of technology, lighter and had greater range than NiMH even though they were £100 more expensive than NiMH.
How does he propose to test these cases that are brought to his notice?
Is he going to rely on 50Cycles to make the decision on a customer-by-customer basis?
I am concerned because I was 'bullied off' by 50Cycles on a legitimate claim I had on a cycle and they were not in the 'mood' to honour Mr. Chings promise to replace a Lithium battery after it defaulted having completed only 80 miles although it was out of guarantee having been 'laid up' for the winter of 2006/2007 (November to Mid- march). "We don't take instructions from Mr. Ching" is how they put it.
I regret my complaints will rattle on because I was not satisfied. Did they think I would 'lie down'?
Peter

I need to make it very clear here. The replacement of course have to be processed through 50cyles and it is also very true they don't take instruction from eZee, and I am expressing here that what eZee current position is, how it is going work depends on the co-operation of 50cycles and the customers as well.

We are replacing with the same Li+ battery from Phylion and NOT NiMH obviously. The warranty of the Li+ battery is backed up by Phylion . This is of course possible up to Shanghai Port, there is no possibility we take it into UK. It could only go into the next container of bikes that 50cycles may or may not order from us.

What I meant is for those customers who have Li+ battery and wishes to purchase NiMH battery we would be willing to provide the charger without charge if that the NiMH battery is supplied by us.

W W Ching

 

[WaiWonChing]

Yes thank you for your detailed response. In my opinion manufacturers are welcome to join the forum and enter any discussion provided the forum is not used for advertising your products (sometimes a difficult balance). The advantage to joining is while you will get negative comments about your product (which are always useful) you will also get positive comments and I am sorry you think we have been hostile.

My experience is similar to Fleccs. I bought a new Li-ion powered Torq in July and the battery failed to charge and was returned for a replacement in February 2007. The second battery seemed pretty weak and when the whole bike was returned for a cutting out problem, the battery was tested and found to be only 8.5Ah, down 15% in under 2 months. The cutting out continued to get worse and I nursed it until November 2007. The battery was never deep discharged (except for conditioning) and charged routinely after 10 miles so fairly easy conditions. I calculated this battery did no more than 130 cycles but the performance was very poor from 100 cycles onward. I have under duress bought another Li-ion battery and this is performing better than the previous battery but due to my previous experience I don't have much hope of it lasting 2 years or 300 charge cycles minimum.

In order to re-gain confidence in these batteries I think you will have to improve the guarantee from 6 months to a minimum of a year or preferably 2 years (80% depth of discharge) to match the Panasonic battery you are competing with for sales. Until that happens I will be moving over to NiMH batteries and so thank you for the offer of a free charger.

Dear Harry,
What would the Panasonic Li+ battery 26V 10 Ah = 260 wh cost ?
Also I also like to know what is the max. load that the Panasonic system runs at, and what the normal load ? 2 amps or 4 amps or 10 amps ? Never mind what they say about their motor is 250 watts, what they are really doing together with the controller ? These are originally designed and build for Japanese grandmothers. We take it up to 20 amps and in such condition it is also very taxing for the battery life.
W W Ching

 

[Tiberius]

Mr Ching,

Thank you for your very welcome and helpful posting. It would be good, and I think perfectly acceptable, for you to appear on the forum. Please do read what has been posted, because quite a lot is complimentary about eZee and its products. On the subject of the Lithium batteries maybe not so, but there is much useful information there for you.

It is interesting to hear that you tested 3 makes of battery and rejected 2 of them. If you read around here, you will see that we do not necessarily think the Phylion Lithium batteries are themselves bad, but that they do not survive the current drain being demanded from them.

You mention testing at 0.5C (5A). I have seen currents up to 18 A (nearly 2 C) on my Torq and it is quite possible that the peaks are higher. I am sure you will be doing your own research but you might like to bear this in mind.

Nick

 

[HarryB]

The warranty of the Li+ battery is backed up by Phylion . This is of course possible up to Shanghai Port, there is no possibility we take it into UK. It could only go into the next container of bikes that 50cycles may or may not order from us.


W W Ching

I am slightly confused about the warranty/guarantee situation. What is the period that Phylion warrant their battery for? If it is more than six months then why would this not be passed on to the UK customer? If it is less than six months, why don't Ezee find a battery supplier that provides a proper guarantee as per the Panasonic/Kahlkoff battery? As I said before, a proper 1 or 2 year guarantee would give the consumer some confidence in this product.

 

[flecc]

Regarding the mention of the Panasonic battery, on the latest version with high power mode, the maximum drain possible in theory would be just over 17 amps, but in practice it's usually more like a peak of 11 amps. The previous motor with only the standard power mode was quoted as having a peak of 16 amps, but again in practice it would usually be around 10 amps. Hence it gives the battery a much easier time.

The replacement cost of the 26 volt Panasonic battery is £305 in the UK currently. While no-one wants high prices, I think we would all rather pay a bit more for a battery that works, than have a low price for a battery that doesn't work well.

I'm sure Panasonic don't design for Japanese grandmothers, their marketing ambitions extend well beyond that limited sphere. In fact they designed the best ever e-bike system, one that could well be emulated by other makers in the interests of greater reliability.
.

 

[HarryB]

Dear Harry,
What would the Panasonic Li+ battery 26V 10 Ah = 260 wh cost ?
Also I also like to know what is the max. load that the Panasonic system runs at, and what the normal load ? 2 amps or 4 amps or 10 amps ? Never mind what they say about their motor is 250 watts, what they are really doing together with the controller ? These are originally designed and build for Japanese grandmothers. We take it up to 20 amps and in such condition it is also very taxing for the battery life.
W W Ching

Yes the battery is £305 for a 26V so proportionally more expensive. It is supposed to last 2 years and that I believe is what the guarantee is on this battery.

Your points about the load on the battery is a good one and you are agreeing with us that Li-ions are not suitable for high power ebikes such as the Torq or Forza. This is the reason we want to go back to NiMH.

Flecc would have a better idea of the exact maximum power of the panasonic unit but I know it is not 576 watts peak as in the Torq. It provides a 1:1.4 ratio of assistance, so if your granny can provide 250 watts then it will provide 350 watts, so not in the same league as the Torq.

 

[WaiWonChing]

Mr Ching,

.You mention testing at 0.5C (5A). I have seen currents up to 18 A (nearly 2 C) on my Torq and it is quite possible that the peaks are higher. I am sure you will be doing your own research but you might like to bear this in mind.

Nick

Dear Nick,

Our bikes takes the amps right until 20 amps max. Peaks, depending on the resolution of the equipment used to measure it, like we do micro-seconds 1/1000 sec) measurements we could find reading of over 30 amps to 50 amps.

We use 0.5C (5A) as a yardstick to measure capacity Ah for QC pupose, because generally the bike runs at about 5 amps in level ground with speed of 25 kmph (16 mph).

WWC

 

[WaiWonChing]

I am slightly confused about the warranty/guarantee situation. What is the period that Phylion warrant their battery for? If it is more than six months then why would this not be passed on to the UK customer? If it is less than six months, why don't Ezee find a battery supplier that provides a proper guarantee as per the Panasonic/Kahlkoff battery? As I said before, a proper 1 or 2 year guarantee would give the consumer some confidence in this product.

OK, clarification needed here. The warranty period of the battery is 6 months up to 80 % of DOD measure with 0.5C discharge. But because of what I just learned on this forum, I have gathered an emergency meeting with Phylion, that we need to do something for those customers out there who have passed the 6 months warranty period, and are in a very unhappy situation, so we very quickly decided to do something about it, and we are making a large lot of replacement battery to cover this. The entend and duration for this offer has not been fixed because we just made a very fast response to the situation.

At this time we think the bell curve on the quality could be broader than what we would like, meaning there are more poor performing battery than we expect. We are investigating.

I would also take this opportunity to talk about battery capacity. Generally battery manufacturer give their battery capacity in nominal terms like say 3.7V and 10Ah @0.1C. When the pack of 10 cells as in our battery we get 37V, but in reality when a pack is put together with muitple cells, the Ah is slightly reduced. So in reality we get 9.5Ah which our Min. standard for a new battery. At 80 % DOD is 7.6 Ah. Neither would you like to find Panasonic to give the full 8.0 Ah on their packs.

I am on an endless quest for better battery suppliers.
At this time there are 2 or 3 other suppliers that looks promising, but one never know until a year or 2 later. But if the supplier ignor us when a problem develops I would just go under. The current best Li+ battery suppliers are from Japan, but we like to break the monopoly let others have a chance, and maybe it could turn out to be better. I least I believe given some time it will happen. Given the price and performance, and support, it was a very good bet and still is. I have of course been in touch with Panasonic many years back, and later on another thread I will write why I stay away from the Panasonic system.

We are now currently still evaluating LiFePO4. We know it is a very high risk to adopt new technologies, it is impossible to have failure ruled out. Valence Technology which holds a larger no. of Patents on this, told me this battery is good for thousands of cycles, with huge no. of references and show pieces, military applications, big projects with auto companies, and used satisfactorily on the Segway from more than 2 years now and etc. The 2 Valence packs I tested were gone with less 50cycles !
We are also evaluating LiMnO and LiCoO compounded polymer battery from Korea, and Li+ from Sanyo, and Li+ polymer from Amita (Taiwan).

We are doing our homework.

WW Ching

 

[Tiberius]

Dear Nick,

Our bikes takes the amps right until 20 amps max. Peaks, depending on the resolution of the equipment used to measure it, like we do micro-seconds 1/1000 sec) measurements we could find reading of over 30 amps to 50 amps.

We use 0.5C (5A) as a yardstick to measure capacity Ah for QC pupose, because generally the bike runs at about 5 amps in level ground with speed of 25 kmph (16 mph).

WWC

Hi Mr Ching,

I too have looked at it on the microsecond timescale. There are large switching transients from the controller. There are both positive and negative excursions of many volts that reach the battery terminals; I didn't measure the peak currents involved but they must be well over 20A. There is a "ringing" at about 3 MHz which I suspect is due to controller circuitry rather than the wiring.

Nick