LifeBatt cells now available for ebike use

bobmcree

10 kW
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May 25, 2006
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Retirement is not all it is cracked up to be, and when an opportunity comes up that is just too good to pass up it is a good reason to come out of it.

This is why I have agreed to become the US distributor for LifeBatt battery systems for ebikes. For those unfamiliar with them, these are 10 Ah cells using the same LiFePo4 technology the A123 cells use, with cathodes made in the same factories as A123, assembled in Taiwan.

These larger cells are much easier to interconnect, using threaded studs on the ends, avoiding the need to solder or weld tabs.

I have personally done quite a bit of testing, some of the results i have posted, and more will follow. There is also independent testing going on right now at Sandia Labs that should be released by the end of January. LifeBatt testing indicates that after 2300 cycles to 80% DOD the cell impedance has grown from about 5 milliohms to about 6.

The best part is they will provide a 2 YEAR WARRANTY on the cells if used with a simple low voltage cutoff bms like the one Gary and I came up with. As far as i know they are the only company offering this kind of warranty.

Toyota has agreed to buy a significant portion of their manufacturing output, so that is a pretty good indication of the quality.

No more hacking up DeWalt packs to get A123 cells with no warranty, and the cost is fairly competitive with what we are paying for cells harvested from new DeWalt packs purchased on ebay for $100.

I am offering the cells right now for $50 each, plus shipping from L.A. The price will eventually come down, but not for several months. For those of you interested right now, contact me off-list.

I will dedicate space on my webpage to the cells, so in a couple of days i should have plenty of photos and discharge curves on bobmcree.com
 
Glad to see your are the new distributor. Just checking because I didn't see it referenced in your announcement, what is the v of these cells?
 
I need to correct an error. the cathodes are made by Phostec, not in the same factory as the A123. pardon my error, as i am just getting to know the cells myself. The cells are assembled in Taiwan, not in mainland China as I believe A123 is.

they are rated 3.3v as opposed to the 3.6v for the A123 cells. i have posted this discharge curve at 2C (20A) before, but here it is again for those who missed it.
The cells are rated 20C, and of course they will only do that for a few seconds, but i have personally verified that they will do it, and at 200A the 3.3v cell produced over 2v, which is in line with the 5 milliohm impedance spec. the cutoff voltage under discharge is also lower than A123, at 2.1v.

There is a version of the TC54 reset chip that is perfect for detecting the 2.1v cutoff, suitable for use in the lvc boards gary is producing from my simple design. As can be seen from the curve, a detector at 2.7v will sense about 85% discharge, providing ample warning before a 2.1v detector shuts down the controller.

The slightly lower voltage reduces the Wh by 10% relative to a 3.6v cell, so 4 of the 2.4 Ah A123 cells is roughly equivalent in power output to 1 10 Ah Lifebatt. Of course this is just a rough approximation. I would never make the claim that these cells are better than the A123 cells; they may even be not quite as good, but you do not have to hack open power tools to get them, or invalidate the warranty by removing them from a pack.

Since I only today agreed to rep the cells I do not have all the information that is available, but I am committed to getting together everything I can find and posting it on my website. People are also welcome to ask me specific questions personally, at my posted email below. I became involved with LifeBatt because I was looking for the best battery I could find for a bike I am building for Jim Parker at Cruzbike, and when it became clear that they needed a rep and I needed to pay some bills, it was a perfect match.
 

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When I get the cash/the price comes down I'll be getting some. Fo' sho'. :wink:
 
This definitely good news, which is why I am going to work with Bob to do complete packs, with built-in LVC protection circuits. Bob and I are also working on a unique charging solution that will ensure that each cell gets a full charge.

Initially, there will be two pack sizes, a 12 cell 36v (40V...) 10A configuration , and a 16-cell 48V (52.8V...) 10Ah version.

Stay tuned... more later...

-- Gary.
 
Retirement is highly overrated :lol: It's good to see an "Insider" involved. Bob, if you could post prices and such on the "EV Business" page under Batteries, I would appreciate it. And let me know how and when they are commercially available, price breaks on bulk purchases, etc.
Thanks,
Don
 
Ok, so each cell is 3.3v and 10ah, right? What is the weight of each cell? If you guys are able to make smaller packs to make them easier to fit into non-rectangular spaces, I would be really interested in using them for my high performance race motorcycle, when I get to that stage.
 
Drunkskunk said:
Great news! This will probably be the battery I go with for next summer's project. Any idea on a rough price for the packs yet?

I'm hoping to be able to offer the 12s 36V/10Ah pack, with LVC circuits for about $625-$650, and the 16s 48V/10Ah version for $825-$850.

For the DIY'ers out there, I will also offer a kit, for about $40-$50, that will include everyting needed to build either pack, including the LVC circuits. I'm not sure whether the warranty will be covered for the DIY kits, but I will check. The complete packs will defintely be covered by the 2-year warranty.

Each pack will have PCBs that bolt to the ends of the cells, both to hold them in place, and to bring all the wiring out to edge connectors on one end. The LVC board will plug into these two edge connectors, and will have a board-mounted multi-pin connector that will be used for charging/balancing. The packs will be covered with heavy duty rubberized shrink wrap.

I'm hoping to pick up a bunch of cells for testing, today or tomorrow. I will get the first boards by the end of the week. I will post pics of the pack construction and the completed packs in this thread.

-- Gary
 
Jay64 said:
Ok, so each cell is 3.3v and 10ah, right? What is the weight of each cell? If you guys are able to make smaller packs to make them easier to fit into non-rectangular spaces, I would be really interested in using them for my high performance race motorcycle, when I get to that stage.

Each cell weighs 359 gm, or about 12.6 oz. I'm guessing a 12s 36V pack will weigh about 9-1/2 to 9-3/4 pounds. The 16s 48V pack should be around 12-3/4 pounds.

-- Gary
 
Stay tuned... more later...

-- Gary.[/quote]

I am interested in the 12 cell pack! What would be the low voltage cut-off for such a pack? Will you ship to Canada?
 
If ebike controllers are set at 29V LVC
and this BMS is set at 2.1v per cell = 25 V
...then the ebike controller will shut off first ?
 
Don Harmon said:
We are glad to have Bob aboard, and will support him 100%.

Don Harmon

Hi Don,
Are we going to see a battery technology progression like we saw for computers?
Twice the capacity and half the price every year? :D
Or are you limited by the chemistry? :(
 
green hornet said:
If ebike controllers are set at 29V LVC
and this BMS is set at 2.1v per cell = 25 V
...then the ebike controller will shut off first ?

the beauty of this simple bms is that it monitors the voltage of each cell independently, so if an imbalance condition occurs that causes a single cell to reach the safe cutoff level before the pack voltage drops to its cutoff level the system will detect that and protect against damaging that cell.

generally the cells are pretty well balanced, so yes i would expect the cutoff in the controller to assert first. for users with a cycle analyst they can program in any cutoff voltage they like.

my intention is to work with gary to provide a bms that asserts a warning signal when the first cell hits a level of about 2.7v under load, warning of 10% remaining capacity, then cuts off the power at 2.1v under load. with a system like this, even when the controller cuts off at the lower level, it will be possible to lower the throttle setting and have enough remaining power to safely get off the road.
 
Hi Don,
Are we going to see a battery technology progression like we saw for computers?
Twice the capacity and half the price every year?
Or are you limited by the chemistry?
_________________
OLIVIER

Not quite. Defininately you will see price affected by "true mass production" but this will take some time to kick in. By the end of next year prices will be coming down as the new entries into the EV market start ordering automotive & aviation packs in large quantities.

The key to all this is building a modern mfg. plant such as the one LiFeBATT is currently building in Taiwan. Much of the existing equipment used to make Li-Ion batteries is not applicable to manufacturing LiFePO4, which is why the cost is so high right now. It takes a huge investment of working capitol to set up an automated battery manufacturing facility to produce a high volume of cells. Most of what you see out there now is basically "hand made" on small assembly lines in China.

With a fully automated plant using robotics technology, we will be able to manufacture a very high volume of quality cells per year - which will bring the pricing down over the next few years to what I believe will be and acceptable level for the EV & PHEV market to become viable.

We already know we can increase the capacity of our cells, but there is a limit to the chemistry which has drawbacks to increasing the power density too far right now. Life Cycles will drop with higher capacity. We will most likey offer several formulas next year of the large format 40138 LifeBATT cell. Stay tuned.

Best,

Don Harmon[/quote]
 
8) Good news for us ebikers.
When shipping to Canada do not use Fedex or UPS, the brokerage charge is too much, only use USPS.
 
OLIVIER said:
Don Harmon said:
We are glad to have Bob aboard, and will support him 100%.

Don Harmon

Hi Don,
Are we going to see a battery technology progression like we saw for computers?
Twice the capacity and half the price every year? :D
Or are you limited by the chemistry? :(

Olivier, the Phostec compagny that BOB is talking is based near Montreal!
you know that?
 
Phostech Lithium will establish a new 27 000-square-feet production site in the city of St-Bruno, close to Montreal, Quebec. Phostech Lithium intends to move its existing activities to this new site in the coming months, aiming to have an installed production capacity of 600 tons of LiFePO4 per year by the end of 2006.
Phostech Lithium actual 7000-square-feet site located in Boucherville, which has production capacity of 100 tons of LiFePO4 per year, will remain in operation until the new site is ready.

Phostech also makes a higher power powder which is what is used in the LiFeBATT 40138 Cells in their plant in Munich, Germany.

Don Harmon
 
At what voltage should charging of these cells be stopped?

Most promising developments. Will certainly keep an eye on this thread!

Larry
 
The slightly lower voltage reduces the Wh by 10% relative to a 3.6v cell, so 4 of the 2.4 Ah A123 cells is roughly equivalent in power output to 1 10 Ah Lifebatt. Of course this is just a rough approximation. I would never make the claim that these cells are better than the A123 cells; they may even be not quite as good, but you do not have to hack open power tools to get them, or invalidate the warranty by removing them from a pack.

This is just plain truth- well done and hope you two will make some good value battery packs. Congratulations on your new position: your honesty along with real world expertise is the best.

Note: This post qualifies for 10% discount :D
 
i will discount the price 10% on the cells right now if you buy 36v/20 Ah.and use an approved bms like the ones gary is making. this would drop the cell price from $1200 to $1080
 
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