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Discussion Starter #1
My main parts supplier still doesn't recommend lithium yet but this may be a year or two old opinion. Says there's no data or not enough about the longevity of lithium batteries.

I figured I'd see what you guys experience is. So how long have you had your pack and what is your average discharge C rate? Any problem with warranty issues?

I know we have lithium in our phones and computers. My only experience is that I'm on a laptop now that has a lithium pack and I can't tell any difference than when it was new three and a half years ago.
 
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There are lots of folks that are beginning to see the merits of the lithium batteries. I think some of your information may be a bit on the older side of this. It has become quite clear that lithium will give you the distance. If set up right you won't be over discharging your pack and you will still retain your performance and may get a bit better. You will loose lots of weight and as long as the batteries last you will be much better off using lithium. I am just starting out using lithium but there are some who have shown that they perform exceptionally well and that after two years the batteries sill perform as new and hold full charges and discharges. They run cool and strong. TS and CALB have a good track record and Hi-Power as well but they are considered the low end of the three but gaining some ground. CALB, TS and GBS are the most common purchased. It is good news that you can now buy CALB cells in LA directly.

I think many still need convincing but I decided to jump on board. I have been unsuccessful at getting more than 30 miles at a decent speed with lead. No matter how many I stuff in my car. My distance did not increase much when I jumped from 72 volts to 96 but I did get better performance. Still crappy distance and one hell of a heavy car. No thanks, I am done with that now. I know I can build. Time to get a viable vehicle together.

Go lithium and have a viable and usable electric vehicle. If you can't afford them yet then you don't have many options. I'd start saving. I did. Long wait too.

Like your truck.

Pete :)
 

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Discussion Starter #3
Thanks Pete. Yea I'm hoping someone here has something lasting a while. It pains me to think I could pay $12000 for a pack and the cells begin dying off in 3 or 4 years. I won't be quite through getting my payback at that point. I think it will take about 8-9 years to recover my money, but it's not all about money. Clean air is something I really appreciate now, every time I see a road truck spewing black plumes of smoke I'm reminded of what I'm doing for those around me when I drive.

I wondered just yesterday how many more beautiful days we will have every year when we get a lot of folks off of petrol.
 

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Hi !

I have had my TS pack for almost two years now and driving it for over 1 and a half year and almost 7000 miles. I have had one cell out of 42 go bad on me. Other than that they work just fine.

But I have no 8-10 year info yet.

Regards
/Per Eklund
 

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Dawn, thanks for your post. I read something very disturbing yesterday referring to lithium ion batteries and that is that they all die off around 2 years. That was very disturbing. I can't imagine losing all the cells after less than 3 years! Here's the link.

I know there were some running Thundersky cells in mid 2008 so that's 2.5 years but haven't heard of them dying so I'm assuming Lifepo4, though very similar is different in that respect and doesn't die off so soon.

That's why I started this thread, to get feedback and hopefully in this case, no news is good news.
 

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Hi !

I have had my TS pack for almost two years now and driving it for over 1 and a half year and almost 7000 miles. I have had one cell out of 42 go bad on me. Other than that they work just fine.

But I have no 8-10 year info yet.

Regards
/Per Eklund
Can you tell us the circumstances of the failure?
Gerhard
 

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This is interesting as I read a post on the NEDRA site from someone who indicated that Li all died after a few years also. I asked for clarification and who he may know in this predicament...but no reply. I haven't read anything like this from actual users.

Perhaps a look through the garage and a few emails to users who may have built their cars some time ago and no longer frequent this and other sites may turn up something....although the chemistry may be different.
 

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Can you tell us the circumstances of the failure?
Gerhard
I actually dont know what happened to that cell.
It just turned into a busbar. 0v but fully conducting.
Another TS owner here in Sweden had one Cell do the same. I sold him one of my spares. I have no spares right now.

But I think I have overcharged some of them.

Regards
/Per
 

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I bought an electric motorcycle based off of 40AH Thundersky Cells back in November of 2009. I believe the motorcycle itself was assembled in the beginning of the year.

I have ridden it about 900 miles (~25 charge cycles). I installed a Goodrum/Fechter centralized shunting BMS to perform top balancing. One day I was using a rachet to unbolt one of the batteries. The ratchet and the bike's frame came into contact. I thought the BMS and batteries were isolated from the frame, but smoke came out of the BMS. I stupidly left it attached and a few weeks later I noticed that two of the cells were at 0V.

So yes, I've had cells die. However, I don't believe it was due to degradation of the batteries, but rather a catastrophic BMS failure.
 

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Discussion Starter #10
I bought an electric motorcycle based off of 40AH Thundersky Cells back in November of 2009. I believe the motorcycle itself was assembled in the beginning of the year.

I have ridden it about 900 miles (~25 charge cycles). I installed a Goodrum/Fechter centralized shunting BMS to perform top balancing. One day I was using a rachet to unbolt one of the batteries. The ratchet and the bike's frame came into contact. I thought the BMS and batteries were isolated from the frame, but smoke came out of the BMS. I stupidly left it attached and a few weeks later I noticed that two of the cells were at 0V.

So yes, I've had cells die. However, I don't believe it was due to degradation of the batteries, but rather a catastrophic BMS failure.
Do you think maybe it was wrench failure?:D I doubt the BMS would protect from that!

Seriously, make sure the pack itself isn't connected to the frame NOR the negative side of the original battery which likely was connected to the frame. The BMS may be powered by the old bike electrical system.
 

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Do you think maybe it was wrench failure?:D I doubt the BMS would protect from that!
Yes, I started the cascade of events, but the BMS perpetuated it. It's one thing for a BMS failure to cause it to simply stop working. This one failed in a way that it engaged the shunt and caused it to actively drain the cells. Apparently if a MiniBMS module fails it won't engage the shunt, so at least someone foresaw this problem and protected against this type of failure in their design.
 

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One day I was using a rachet to unbolt one of the batteries. The ratchet and the bike's frame came into contact. I thought the BMS and batteries were isolated from the frame, but smoke came out of the BMS.
So I guess you never read the memo from Mike Brown about wrapping all of your wrenches with electrical tape BEFORE working on the battery pack ?

KJD
 

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I doubt you're going to find any long term LiFePO4 pack information since they simply have not been available for very long. Second hand info from Dave Kois says he has some 4-5 year old packs still going strong. I've heard of some bad cells from TS users but not from SE/CALB users.
 

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I had a LiMN pack that had 80% capacity remaining after mostly sitting on the shelf for 5 years, the pack was also abused occasionally, when I felt sadistic.

Statements like "all Li dies after 2-3 years" just indicate that the writer doesn't know much. It depends greatly on chemistry and storage conditions.

Li batteries in laptops usually die after 2-3 years due to constantly being overcharged and cooked by the processor. Although I was pleased to find out that my new Samsung laptop has a setting for only charging the battery to 80% in order to extend battery life, very neat. It will be interesting to see how long the battery lasts.
 

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So I guess you never read the memo from Mike Brown about wrapping all of your wrenches with electrical tape BEFORE working on the battery pack ?

KJD
Haha. It was wrapped in electrical tape. However, having rubbed against sharp corners it was torn in some places, and maybe the end was coming loose. I would actually recommend heat-shrink tubing as there's no chance of it unraveling and it's generally tougher.

I have my 24 TS cells out of my bike now as I'm changing out the controller and redoing/shortening some wire runs. Each block of 4 cells I'm temporarily wiring in parallel and using a VoltPhreaks 2A single-cell charger on. Although, apparently, I could have wired all the batteries in parallel, and then also used all six chargers in parallel. The only advantage to that would be if the chargers weren't calibrated the same.
 
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