Long Term Test Outcome - eZee battery

[HarryB]

By the way A to B gave a mention about the battery test in the last issue - I didn't want to say anything as I know you didn't want talk about your testing. Good work anyway I am sure new Ezee owner will have a lot more confidence in their batteries now.

[flecc]

Originally Posted by john

Flecc, Do you think it would be the same for 12 calender months? I think we have seen Lithium battery degrading due to time alone as well as use. I'd be interested in your thoughts on that.

I would think there'd be some small further loss John, but given that the best examples that have been around for a while like Panasonic-Sanyo and BionX batteries with very little loss reported, I don't think it will necessarily be serious. When questions were asked about the BionX battery in here some while ago, some responses indicated no readily detectable loss in range at over two years old. I've also never seen complaints on the types of Panasonic units using lithium for more years than that.

50cycles may also have some relevant information, since they imported the Panasonic Will and Honda Step Compo Li-ion folding e-bikes in 2004, and I know that Tim has still been riding the Step Compo around London at times. It's highly unlikely they will have bought a new battery from Japan, so there's a life indication of nearing four years for those top grade batteries, meaning low loss over time.
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[flecc]

Originally Posted by HarryB

By the way A to B gave a mention about the battery test in the last issue - I didn't want to say anything as I know you didn't want talk about your testing. Good work anyway I am sure new Ezee owner will have a lot more confidence in their batteries now.

Yes, I saw that Hal, from which you'll gather that I'd been in touch there.

I don't know about any guarantee change, but I wouldn't be surprised at unwillingness to break ranks, and so sticking with six months which is the most widespread. Personally I don't think guarantees matter quite so much now since indications are that these batteries will sail past a year and probably be usable at two years or more as you'll see from my reply to John above.

Although I haven't mentioned it above since I didn't want it to appear I was hypeing it, the outstanding thing for me has been the power delivery of this test battery. Pointing it at the toughest of long climbs with a standing start, it slogs up without ever showing the slightest sign of tiring through chemical exhaustion, very different from previous versions, and even now that has changed very little.
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[Matt]

Originally Posted by john

Flecc, Do you think it would be the same for 12 calender months? I think we have seen Lithium battery degrading due to time alone as well as use. I'd be interested in your thoughts on that.

First off, a great job you did testing the battery, you must have been dying of bordom at some points.

This was going to be my question and I know you've already answered. I'm now onto my 5th battery for one of my laptops. (it's 5 years old now) What I found was it didn' really make too much of a difference how frequently I discharged it, until it was around 9 months old, and then if I discharged it down to below 10% after that it would really kill it and I would need a new one.

It would be great if you continued with the testing for a few more months to see what happens, or perhaps even better, just test it on occasions so you're basically just testing the effects of age and not use.

[flecc]

Some days it was really boring Matt, but luckily the countryside is pleasant round here and I know many of the local farmers so I'm not always alone while out.

My original laptop battery is nearly four years old* now, and I often discharge it fully without failure. I'm wondering if your experience is something to do with the BMS on your laptop.

I doubt if there'd be any problem like that on this battery given the many types that do last for much longer as said. However, it may not be in my hands, this one was intended to go back to China for lab checks on capacity etc. Given the good results that may not happen, and if not I'll continue using it so will find out in time.

I just can't see any possibility of that though, given how strong it remains I'd bet on it going to well over 400 charges as I'm well past half that, and 400 to 500 charges is a normal life for Li-ion manganese. Remember that many of the charges I've done have been full ones since I've been riding with my battery spare in the pannier so able to empty the test battery to cutout on many rides.

* I use cold storage for the periods when it's not in use for some while.
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[WaiWonChing]

Hi,

Sometimes I read with great astonishment how people one would purchase a pack of battery for example a LiFePO4, and if it did well, and results posted, and then there is a chorus of cheers and hand clapping.

My company spent a lot of money and time testing batteries, you could get SEVERAL samples tested out well, and then even, a few lots, with hundreds of packs or even over a thousand packs without any problems (except certain mishandling such as bad soldering or something) , and then suddenly disaster strike. There are of course many factors that could screw up the battery in the manufacturing, the purity of the chemical composition, the particle size and particle sizes distribution, the thickness of the coatings, the separators and etc and etc. Therefore, I know it is very critical to find and source from a extremely well managed company, and even then there is still no guarantee, as what happened to us with some deliveries of Phylion. Those that does not pass the scrutiny I do on paper first would not get tested in my company, there is simply no point to waste the time and money.

Example I have tested LiFePO4 since more than 2 years ago, and continue to test them as new producers appears. But we don't simply jump into it if a couple of units looks OK. You will be suprised how big names in this product failed with 50 cycles when they were promising 1000 or more.

Then beside laboratory tests , we need to do field tests, and this is more difficult, so I picked a couple of customers who have exceptional experience and expertise like Flecc, and some customers who have terrible experience with our batteries but enough standing to give me a fair and truthful report without the aim to destroy me if it still goes wrong.

Now, to easily read the mysterious codes on the Phylion battery , it is very simple . Example The serial no. S/N: JGJHBF 100082 = 070826 = 2007, Aug, 26th the 82nd battery of the day.
J is 0 , ABCD... is 1234 and the last 2 digits is the nos. of battery done that day.

eZee is now delivering Li+ polymer battery. We made no new contract in 2008 for Phylion battery pending on the final outcome of the 1000 pieces that has been 'corrected' we are still delivering from 2007 contract until end July 2008 to some countries. I will decide on Phylion again when I see results for 1000 units, and some of them under the microscope.

As of 2008, we give warranty on the battery for 12 months up to 70% DOD discharged at 0.5C or 5 amps.

Wishing everyone a good time with their electric bikes.
W W Ching

[Matt]

Thanks Flecc. The laptop I have basically has a desktop processor in it which I don't think helps as it puts a lots of strain on the battery.

[flecc]

Thanks for that coding information Wai Won, I hadn't realised the alpha-numeric significance.

Also that improved warranty cover, though hopefully that won't be needed given how well my test one has performed.

I well remember Ken mentioning the LiFePO4 trialling but nothing coming of it.
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[flecc]

Originally Posted by Matt

Thanks Flecc. The laptop I have basically has a desktop processor in it which I don't think helps as it puts a lots of strain on the battery.

That's true Matt. I've been tempted to upgrade a few times but still struggle on with an early version 1.6 Celeron, but don't have to use it too much.
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[joab]

Thanks for the explanation of the battery serial number.
My battery was build on September 21, 2007. See my test under EZEE bike conversion kit test

Looks I have the same battery but a 10ah.