Lifepo4 batteries

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Mar 29, 2007
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Tauranga
Found this website today not sure if it has been listed here before but prices look reasonable


http://www.goldenmotor.com/batterypack.htm
 
Sent a email to GoldenMotor People and USA distributor listed on http://www.goldenmotor.com web site a few weeks ago. Still waiting for reply. Canada distributor does reply to email. They "only sell the conversion kits" Sent another email today to GoldenMotor People and USA distributor.

Thinking of buying High Power Polymer Li-Ion Module: 37V 16Ah 40 Amp Rate from http://www.batteryspace.com
PA090221.jpg


Dimensions 6.3" x 4 .6" x 3.4 " Weight 2540 grams (5.6 Lb) is the smallest and lightest I have found. Planning on using two of these to make 72V 16Ah

$789.95 times 2 = more then a sane person would spend on batteries :eek:

I read Reid Welch's long story about his bad battery http://endless-sphere.com/forums/viewtopic.php?t=505 Hope this was one bad apple in the pile? Has anyone had a good experience with batteryspace.com? They do reply to emails. Called them. Talked to a guy who remind me of the guy in a Chinese Restaurant. Who cares about hard to understand English. The food tastes GOOD!

BatterySpace web site say "Please note this battery is for R&D use only and NOT for individual customers" Lets all thank Reid Welch for helping BatterySpace with there R&D research and development. Shouldn't BatterySpace be doing there own R&D?
 
In case you or anyone else may not be aware, batteryspace has a forum on their website where you can post questions & read about other customers experience with their products. They seem to make a good effort to be responsive & helpful, but as you've noted because of the language hurdle, you don't always get quite the response you're looking for.
 
USA distributor from GoldenMotor called today. Li-Polymer battery packs not for sale in US yet. Yet. Come on all you Electric Bike Manufacture People what's the problem? Can you not figure out how to transport batteries? Power tool, laptop, cell phone makers got that figured out. Can you not figure out how to test batteries? Ask Fechter. Not sure how to charge batteries? Ask Xyster? Nice job with charging cords, Xyster!
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Would also like a small plastic case like all the cordless power tools have.
 
Can you not figure out how to test batteries? Ask Fechter. Not sure how to charge batteries? Ask Xyster? Nice job with charging cords, Xyster!

:lol: :lol: :lol:

Thanks!

As for Batteryspace, one parallel subpack of 16 cells of my 300 lithium 18650s are BS's 2000mah model, all the rest are all-battery's 2200mah model in 15-cell parallel subpacks. I haven't had any problems with either once I figured out I shouldn't discharge below 3.7V (I have no BMS, which sometimes like with Reid's BS pack, could be a good thing...).
 
thunder-logo.JPG


Lithium Iron Phosphate (LiFePO4)

Model Dimensions Weight Price
LFP-40 116×46×190 mm 1.5 Kg $100

These cells are 40 Ah; nominally 3.2 volts, although they range from 4.25V to 2.5V

4 cells will make a 12.8 volt pack, and given the 95% efficiency of lithium vs. the 65% efficiency of lead are roughly equivalent to a 60 Ah lead-acid battery.

http://www.electricmotorsport.com/PARTS/parts.htm


lfp40.jpg
 
All this time I thought it was the polish name Thundersky :)

Isn't there a Thunder Sky yoo-hoo! group dedicated to these or have they disbanded?
Because last I heard (from John Schuyler I think it was) that Thunder Sky no longer warranteed them for high drain EV use.
 
Toorbough ULL-Zeveigh said:
Because last I heard (from John Schuyler I think it was) that Thunder Sky no longer warranteed them for high drain EV use.

From what I've read the first few years of this battery product was terrible. The product did not live up to expectations. But their latest version has supposedly fixed those problems.

I'll have to email ElectricMotorSports and get his opinion... Todd Kollin is unlikely to promote "crap" and now he seems to be endorsing them...
 
The new Thunderskys are different than the earlier versions. These look much more promising. Todd and Roller are out thrashing some packs now, so we'll see how they hold up.

Now if they could just get the price down, but they might already be more cost-effective than lead acid if they perform as advertised.
 
Safe: Thanks for the battery link. I've been checking regularly to see when these were going on sale. Must have just updated.

If you're planning to email Todd could you ask about charging at the same time? Is it possible to use standard lead acid chargers?
 
Here's some more info on these batteries -

We've gotten some sample units in all the sizes (40, 60 and 90 Ah). We put the 90s in the E1 bike (converted R1) and the 40s in a Super Motard. Haven't done much testing in the E1 - it's still being worked on. They work well in the Motard, although it's only pulling ~ 120 amps. This may be a controller issue, as they will put out 300 amps into a load tester.

As far as charging goes, there is no BMS. The packs should be charged to 4.15 - 4.25 / cell; the conventional thinking (I wouldn't call it wisdom yet) is that at 4.15 you don't get quite the full capacity, but better cycle life. Ideally you want a charger specifically tailored to the pack. Zivan chargers can be configured to the exact curve that you want, but are expensive.

You can use a standard lead/AGM charger, but you've got to match the number of cells to the charge profile, and this is where the problem comes in. It's never an exact fit voltage wise, unless you get lucky. For example, the Soneil 4820 has a finish voltage of 58.34 volts, giving a very nice 4.16 volts/cell in a 14 cell pack. But even this doesn't correspond to the curve on the TS site. What they spec is constant current up to the finish voltage, and then hold that voltage until the current drops to 0. But that isn't what AGM chargers do - they taper current up to the finish voltage, and then stop charging.

What the implications are here is unknown at the moment - we need to do more work and testing. These are early days - it's not clear to me yet exactly (or even close!) what methodology to use without spending thousands on sophisticated battery testers/cyclers. At least I can run profiles on what we're testing - I'll post when I've got some hard data. Right away we should get a drain brain on some bikes - and now they ain't shipping outside of Canada, damn it.

FYI, we're still waiting on the bulk shipment - they may not be here for another 2 to 4 weeks. I'll keep you posted.
 
The Soneil 4820 profile:
 

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Sounds like a simple voltage regulated, current limited power supply would work as a charger. A lot of the surplus ones I've seen are adjustable over a small range.

Cool graph. What were you using to log the data?
 
Is it me or do these seem pretty heavy? Are we saying here, for example, that a 48V pack would require 14 of these cells @ 1.5 kg each? Although I guess they ARE over 3 times the Ah's I'm used to so that might explain it.
 
I agree about the simple power supply, if you can find one with the voltage you're looking for. It will mean longer charge times, as most supplies have lower amp output - but that's ok.

I've thought about testing single cells that way - with a bench PS - but it's going to be a long process at only an amp. This would only be if I were going to use a CBA - at 150 watts it would put a good load on a cell. Better to test a full pack, but then we're in Drain Brain territory. Good news - they will be shipping when the new DB 2 is ready - hope to get a beta unit in 3-4 weeks.

The data was logged with a Fluke 123 Scopemeter, and the graph is a screenshot right off the PC software. Very handy tool, that - it will also measure phase difference directly, which is a godsend when working on AC systems.
 
safe said:
thunder-logo.JPG


Lithium Iron Phosphate (LiFePO4)

Model Dimensions Weight Price
LFP-40 116×46×190 mm 1.5 Kg $100

These cells are 40 Ah; nominally 3.2 volts, although they range from 4.25V to 2.5V

4 cells will make a 12.8 volt pack, and given the 95% efficiency of lithium vs. the 65% efficiency of lead are roughly equivalent to a 60 Ah lead-acid battery.

http://www.electricmotorsport.com/PARTS/parts.htm


lfp40.jpg

I've posted link to their site one month ago:
http://endless-sphere.com/forums/viewtopic.php?t=774&highlight=

BTW that topic should be moved to Battery Technology also.
 
Thanks for the info on charging Patrick!

Just doing some back-of-envelope sums – the results are very interesting, assuming these batteries deliver what Thunder Sky promise.

If I were to replace my lead acid battery pack with LiFe I would go for 20 of the 60Ah batteries, giving a nominal 64 volt, 3.84 kWh pack.

Taking my energy consumption as 85 Wh/mile, which is what I get in fast city riding, averaging 35 mph, this would easily give me 30 mile range without exceeding 70% depth of discharge. Cycle life at 70% depth of discharge is 3000 cycles according to Thunder Sky, so possible lifetime range is 90,000 miles.

Assuming the 60 Ah batteries cost $150, a pack of 20 would be $3000. Total cost of charging over 90,000 miles at $0.02 per mile adds a further $1,800. Grand total, say $5,000.

That's a lot of money, but 90,000 miles worth of petrol at UK prices ($8 per gallon!), assuming 70 mpg for the ICE version of my bike, would cost close to $10,000.

Amazing! I'll actually be saving $5,000 by buying a box of LiFe batteries. So when did you say those batteries are coming in Patrick? :twisted:
 
These batteries look impressive.

I've already started bulding the frame for a NiMh bike that would have the "D" size cells hidden inside the frame, but if these are as good as they claim I'm thinking I might drop everything and rethink a new bike.

The price-performance of these looks very good and they look durable and easy to use.

Plus it seems like there has been a big spike in NiMh prices. That sucks! At the very moment I was thinking of buying the batteries the price makes them no longer such a great deal.
 
Hey Malcolm -

I like the way you think. "It's not how much you spend, it's how much you save!". We love customers like this. :D

We do still have a crate of 60s - we're using it as a coffee table. I'm trying to sweet talk Todd into letting me "test" them - the phrase "Out of my cold, dead hands" comes to mind.

Seriously, there are a couple of assumptions that bear looking at. One is that 90,000 miles on a bike is a lifetime of use. Another is that the cells aren't proven - if cycle life turns out to be 1500, somebody is gonna be pretty disappointed after shelling out more than two thousand pounds (don't forget the charger). I'm just trying to remove all the hype in this industry; I think everyone will be much better served if the real facts are on the table.

What we have on order are the 40s. These will give more flexible mounting configurations, and could even be doubled up for 80 Ah packs. These batteries are not small - if you look at the E1, there are enough yellow bricks to pave the road to Oz.

That being said, if you'd like to be an early adopter, we won't stand in your way.
 
Thanks for your honesty Patrick, it's much appreciated.

My calculation was a little tongue in cheek. I just wanted to illustrate how electric vehicles could actually make sound financial sense for urban commuting (preaching to the converted, I know). I don't have the cash to spare at the moment, and even if I did I would be looking for a lighter donor vehicle first. Your point about 90,000 miles being a lifetime of use is a good one though. If these batteries were good for that long I could actually be passing them on to my kids!

Safe: these batteries would be great with your new machine. Perhaps while you're rethinking it you could add some suspension :wink:
 
You know I once had a chat with an old man who came to clean out the furnace. It would seem that the cheaper a client is, the more they spend upfront on a new furnace because a better furnace ends up being cheaper over a decade or two.

I guess batteries are kinda similar, though for now I'll keep burning oily rags, broken chairs and kindred combustibles...
 
ElectricMotorSports is charging $100 for the 40 Ah battery.

:arrow: Anyone know who sells the entire spectrum that ThunderSky offers and what is the lowest price they charge?

Since this is a chinese company I doubt that a direct purchase would work out. (I'm guessing that $100 is near the best price you can get, but I could see it being $85 somewhere)
 
safe said:
These batteries look impressive.

I've already started bulding the frame for a NiMh bike that would have the "D" size cells hidden inside the frame, but if these are as good as they claim I'm thinking I might drop everything and rethink a new bike.

The price-performance of these looks very good and they look durable and easy to use.

Plus it seems like there has been a big spike in NiMh prices. That sucks! At the very moment I was thinking of buying the batteries the price makes them no longer such a great deal.

I did extensive research before buying my NiMH packs. There's always something better on the horizon, so it all depends on how quickly you want to finish your project.
I figure by the time I get to 500 cycles, new technology will be proven, and the price will have dropped.
 
Lowell said:
I figure by the time I get to 500 cycles, new technology will be proven, and the price will have dropped.

It's definitely a moving target. The problem is that the NiMh batteries were once only $5 and now they are $6.75. So for just 80 batteries that's a $140 jump in price. This increase takes the advantage out of NiMh and starts to make the ThunderSky choice look good. For a little less total Watt/Hours I could get the Lithiums and that would require a completely different frame... more like the one I have now... that would need to be more like a Ducati tube frame. My "DeltaBox" design is very narrowly specific to NiMh.

I just never imagined the price would go UP... I always figured that prices go down... and I wonder what is causing this? Supply and demand? Were the $5 batteries some year old stock and that's the big reason for the low price.

And what about that 14 Ah NiMh company that everyone's been wary of?

I did get an email response when it was about how I might purchase something. When I asked about the 14 Ah rating I got no response.

Looking at their Ebay responses it looks like they had a really good record until the last few months when they couldn't keep up with the orders. They might be simply understaffed for the volume of business they are getting.

So there's always the possibility of risking buying from them... :shock:
 
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