LiFePO4 Battery Showdown!

[Drunkskunk]

The first photo shows the pack next to a 36v 12 ah sla rack pack. The 29 lb. sla would deliver about 1/3 less power than the 19 lb. LifeBatt, but mounting the larger battery might be a bit difficult on many bikes. The substantial molded case is modular so the cells can be stacked in rows and columns and bolted together, so it seems like one possible solution will be to split the 36 – 10 pack into two 18v packs and mount them in panniers that way. This would provide better balance and still leave some space in the panniers for cargo.

That may be the biggest problem with the Lifebat. I run 48V/10Ah worth of SLA in that same bag. There's just no way I could carry that amount of Lifebat on my bike.

Bob, do you have any plans to sell your cells without that case? the case looks well thought out, but in the world of Ebikes, physical size is probably more important than actual weight.

 

[bobmcree]

The first photo shows the pack next to a 36v 12 ah sla rack pack. The 29 lb. sla would deliver about 1/3 less power than the 19 lb. LifeBatt, but mounting the larger battery might be a bit difficult on many bikes. The substantial molded case is modular so the cells can be stacked in rows and columns and bolted together, so it seems like one possible solution will be to split the 36 – 10 pack into two 18v packs and mount them in panniers that way. This would provide better balance and still leave some space in the panniers for cargo.

That may be the biggest problem with the Lifebat. I run 48V/10Ah worth of SLA in that same bag. There's just no way I could carry that amount of Lifebat on my bike.

Bob, do you have any plans to sell your cells without that case? the case looks well thought out, but in the world of Ebikes, physical size is probably more important than actual weight.

they are not "my cells" LifeBatt is privately held, none of it by me. i bought the pack for jim for his bike because i think it is the best deal right now for somebody who wants a cutting edge solution where initial cost is not the primary issue, but rather operating cost over the long term, and using the best battery solution we could find today.

the original spec was a quite a bit smaller than the pack turned out to be, but they have agreed to warranty the cells in this case if i remount them. i cannot say for sure if they would do that for another customer.

Don Harmon of LifeBatt told me they do intend to sell the cells to the ebike market, and that could happen first quarter next year. They are considering having just a couple of people to interface with the ebike market, and I would love it if we can work something out. At this point I am just putting a bike together for Jim Parker of Cruzbike and he paid full price for the battery to LifeBatt. They sent me a prototype pack with no bms and a loose cell that i need to return after testing, and jim's completed pack with bms is being shipped tomorrow.

i am working on several mounting options for the cells on the cruzbike, and will let you all know how it works out. the cruzbike is a wonderful platform for power assist, as anybody who has seen mine can attest. i will get a page on my website devoted to the lifebatt in the next few days, and will post some more photos and data here.

the lifebatt 10 ah 3.3v cell has stud mounts so there is no issue of soldering to the cells. they use brass round thread-on contacts so that the cells drop into the modular holders, but for our purposes the cells can be wired together with circular lubs and multiple nuts/washers.

 

[recumbent]

It almost looks like we can screw them together by useing mechanical couplers and assemble the batteries in long tubes, sort-of. Then, attach these "tubes" to each other, in my fantacy anyway.
Lots of potential for these batteries. Time flies by quickly, longevity is something I would invest in, and less garbage in the long run.

 

[magudaman]

I think the high cost of these new batteries is justified because of it long life. I purchased my a123s for a total of around 500 dollars and that doesn't include the hours of modification and testing. If I had a steady income I would love to have simple plug and play ready to go lithium system and of course would pay extra to get to that point. My 500 dollars only got me 2 hour charge time and 280 watt hours. If I had went lead, it would have only cost me around 60 if not less. With lithium we are leading the forefront and it will be expensive to be on that forefront. I'm sure price will come down as time goes on. I mean heck since I bought my A123s lot of new lifepo4 has come on the the market with 1/3 the price I paid.

 

[Beagle123]

I think Don Harmon has hit on the ultimate answer to EV battery issues.

His product will allow us to create larger better connected battery packs so we can build better vehicles in the future.

The biggest problem we face as builders is making high-power battery packs. He has a great solution. By creating battery packs that can be linked together like "legos," he's made an incredible solution.

If you want a really good bike, how do you think we're going to get there?

Everyone soldering a bunch of AA batteries together? Not!

Hopefully, in the future there will be <b><u>big batteries that we can buy that can be linked together</u></b>. Don has taken the first step.

Also, as many of you know, the oil companies are blocking production of good batteries. So there won't be a corporation coming along to make an electric car, or bike. The only way a good electric bike or car will amke it into the marketplace is by a smaller company forcing it onto the market.

The only way a smaller company can do that is to have components like this at its disposal.

Get it?

And on a more personal note, I'm sure Don Harmon isn't making a fortune doing this. If he's like most EV people, he's working in the EV field because he beleives it's worthwhile. I bet he could be making more money elsewhere.

 

[Battboy]

And on a more personal note, I'm sure Don Harmon isn't making a fortune doing this. If he's like most EV people, he's working in the EV field because he beleives it's worthwhile. I bet he could be making more money elsewhere.

Thanks, Beagle - So far I have made ZERO dollars on the LiFeBATT venture! We are doing this of course to make some money down the line or it would be madness. As many of you have surmised by our investment in the tooling and the molds for our cases, the target market is the electric vehicle business. Mainly the new electric cars which will be coming out in small production batches by some new small car companies in the near future. Also new electric motorcycles will be using LiFeBATT very soon.

We are also working on a way to make our Cells Packs & Chargers available to the e-bike builders. As our production volume comes on-line we hope to reduce the price point we now have. Until then, it has to stay where it is - as we believe the value proposition of LiFeBATT must be first class from the starting gate in order that we set the standard high for this category of battery product.

We are always looking for suggestions, and we listen to what e-bike people say, even though we don't argue our price point. Those who feel they can get a better value or a "cheap cell" will buy from China at their own risk regardless of what our price point is. There are countless examples of ways you can all build packs from power tool packs that seem to work fine for e-bikes. We start with Cells that are much larger than 18650 power tool packs - so we won't try to compare grapes & watermelons

Thanks again, Beagle and let's all hope LiFeBATT can make a contribution to electric vehicles that will benefit the planet and the future environment.

Don Harmon

 

[Ypedal]

Quote "
Be Glad to: Monsoons in Taiwan & Independence Day is over now so we will be talking to the factory tonight and I am requesting a more detailed report from their engineers on the tests they conducted. The 3 month test period just ended last week. Look for a meatier report to be posted here by Friday.

Best,

Don Harmon

End Quote "


Uhm... i beleive this is Friday !!!

 

[Battboy]

Quote "
Be Glad to: Monsoons in Taiwan & Independence Day is over now so we will be talking to the factory tonight and I am requesting a more detailed report from their engineers on the tests they conducted. The 3 month test period just ended last week. Look for a meatier report to be posted here by Friday.

Best,

Don Harmon

End Quote "


Uhm... i beleive this is Friday !!!

Uhm- I can only push the engineers so far and have to be patient since they DO have much higher priorities right now getting our new production line up & running! Should have something from them by Monday or Tuesday. Patience is a virtue :lol:

Don

 

[Ypedal]

I'm such an information whore... but i understand lol... I'll keep poking !

 

[Beagle123]

Hi Don:

I'm a huge fan of what you are doing. I beleive making a "snap together" solution is awesome.

I do have one suggestion that could make your product very attractive to ebikers: If you could sell individual cells and offer ones with a female, threaded terminal on one end. Then we could simply buy the cells we need and screw them together end-to-end. Ideally the male end would be thicker and shorter so the cells are close together.

I dream of the day when I can buy 100 big cells, sscrew them together (with perfect connections) in an hour, and drop them into my bike.

I'm getting ready to send my 90 cells to spot-weld my packs together. Its going to cost me about $350. And I already paid $1400 for the cells.

Keep up the good work.

 

[brandonh]

Where are you sending the cells for spot-welding?

 

[Beagle123]

I was thinking about using Michael at bigerc.com. I'm not sure what I'm going to do now. I have to work out my charging plans before I build my packs, and I'm confused.

I have 91 emoli cells in my garage.

Any suggestions?

 

[dirty_d]

i saw save yourself $350 and solder them together

 

[bobmcree]

after some testing and disassembly of the LifeBatt pack, i have come up with what i think is a good simple way to mount it on many bikes that might have problems with the standard pack configuration. the 36V 10Ah pack is not that heavy at <20 lbs, but it is a big block that could be difficult to balance.

splitting the pack into two 9 lb pannier units each about 8" x 4" x 9" will provide many more mounting options. the attached photos show the first prototype. the molded pack modules have provision for transverse connecting rods, and those can be used for mounting the pannier units directly to the rack for optimum support, leaving the pannier sacks free for luggage.

I have noted previously that i am entertaining an offer from LifeBatt to act as their ebike distributor. Anyone interested in contacting me about using their packs on an ebike in this or any other configuration can email me directly to bob@bobmcree.com. I do not work for them yet, but I do want to help put together my ebiker friends and good batteries.

 

[oatnet]

Look for a meatier report to be posted here by Friday.

i beleive this is Friday !!!

Uhm- I can only push the engineers so far and have to be patient since they DO have much higher priorities right now getting our new production line up & running! Should have something from them by Monday or Tuesday. Patience is a virtue :lol:
Don

Hi Don!

It's Tuesday, and I am eagerly awaiting your 'meatier report' . I am sure the factory's engineers are eager to share the details, now that they have conclusively shown that Chinese LiFe fails after 3 months of testing.

As per your statements, this would prove that your product is the only viable Life alternative out there, so I bet the engineers can't wait to publish and shut up all the NaySayers that have been plauging you.

-JD

 

[Battboy]

Look for a meatier report to be posted here by Friday.

i beleive this is Friday !!!

Uhm- I can only push the engineers so far and have to be patient since they DO have much higher priorities right now getting our new production line up & running! Should have something from them by Monday or Tuesday. Patience is a virtue :lol:
Don

Hi Don!

It's Tuesday, and I am eagerly awaiting your 'meatier report' . I am sure the factory's engineers are eager to share the details, now that they have conclusively shown that Chinese LiFe fails after 3 months of testing.

As per your statements, this would prove that your product is the only viable Life alternative out there, so I bet the engineers can't wait to publish and shut up all the NaySayers that have been plauging you.

-JD

Hang a little longer - we got some bigger fish frying at the moment! I will come through with it or have to commit "hare kare" 8)

 

[vanilla ice]

Is that somewhat like hara kiri?

 

[Battboy]

Is that somewhat like hara kiri?

Some say tomato - some say tomato, put an "e" on the end and you will be correct LOL!

 

[OneEye]

"hare kare" is the traditional art of raising rabbits for show and breeding. Many consider it a fate worse than death.

 

[OneEye]

Oops, I neglected to consider Don's local dialect, in which "hare kare" is the art of cosmetology. So either he will wash his hair or become a barber/hairdresser.

 

[bobmcree]

I received the 36v 10 ah Lifebatt pack with the bms yesterday, and of course I had to open it up and take a look. The bms looks to be very capable, using an Atmel Atmega 16L RISC processor that has 16k of flash eprom and an 8 channel 10 bit adc.

The bms has a set of 4 IRF104 fets that can disconnect the bottom end of the 4 cell pack from the load. There is a soldered in 50A fuse setup made by paralleling a 30A and 20A automotive fuses that would be a pain to replace. I don't know if there is over-current protection built into the bms, but the hardware is there to do it. A pair of high quality .005 ohm shunts let the processor measure the pack current in addition to the voltage on each cell.

I have a spec of 2.1v for the LVP and 4.0V for overcharge protection. I can see how this bms will handle the LVP with the negative output cutoff and a piezo buzzer, but I cannot tell for sure if there is any overcharge protection or balancing built into the bms. I have put in a request to the factory and expect an answer soon. There is enough hardware on the bms that I expect they are doing some fairly sophisticated protection, and may be doing some kind of balancing, or be planning to add those capabilities in the future.

Each 4 cell 12v sub-pack has its own independent bms, meaning there are a couple of redundant current sensors and fet switch sets in a 36v pack. I am hoping to work out a way to modify the bms so that we can split a 12 cell pack into 2 pannier modules instead of the original 3, and that requires some modifications to the bms, or replacing it with something a bit simpler and smaller. I am reluctant to do that, since these units are obviously built to last thousands of cycles and it seems there is a pretty good possibility we can work out a way to use them with just a bit of extra wiring.

The 16k flash memory in the RISC processor can have new firmware flashed on-board as the bms requirements are refined. the bms in each 12v LifeBatt sub-pack is more complex than many motor controllers.

 

[CGameProgrammer]

Grrr, why would anyone solder a fuse? Maybe you should request that the factory change that if you can, especially if they want to significantly increase production; best to catch these issues as early as possible.

I don't see the usefulness in splitting a 36V pack in two. 18V per subpack? That's very uncommon. 12V increments are very useful and versatile, and many of us use at least 48V so that can be split in half anyway, as can 72V, etc.

I can't believe 36V 10Ah weighs 18 lbs though. That's heavy. Can you weigh the cells, BMS, and case separately and tell us the weight of each?

 

[oatnet]

I can't believe 36V 10Ah weighs 18 lbs though. That's heavy. Can you weigh the cells, BMS, and case separately and tell us the weight of each?

I missed that 18lb stat! So 36lbs for a 72v lithium pack .

I have to check, but I am pretty sure that my 36v10a LiMn from FalconEV weighs 10.2 lbs, and is packaged in a solid metal case. I think the 15ah LiMn was 12.5lbs, so on them the case counts for a good bit. I wonder if that is the 'case' with these life packs too, I second CGame's request.

-JD

 

[Toorbough ULL-Zeveigh]

Grrr, why would anyone solder a fuse? Maybe you should request that the factory change that if you can, especially if they want to significantly increase production; best to catch these issues as early as possible.

I suspect a non-solder fuse would require manual insertion & would actually slow down production with the added step.
Plus there's the added size & cost of a fuse holder.

 

[bobmcree]

Grrr, why would anyone solder a fuse? Maybe you should request that the factory change that if you can, especially if they want to significantly increase production; best to catch these issues as early as possible.

I don't see the usefulness in splitting a 36V pack in two. 18V per subpack? That's very uncommon. 12V increments are very useful and versatile, and many of us use at least 48V so that can be split in half anyway, as can 72V, etc.

I can't believe 36V 10Ah weighs 18 lbs though. That's heavy. Can you weigh the cells, BMS, and case separately and tell us the weight of each?

first, splitting the case is being considered for balance and ease of mounting, not to get 18v. the pack is bulky and splitting it in half for mounting in panniers seems like a good idea for some applications where there is not a good place to mount the large single case.

second, the 12 cells weigh about 9 lbs, and the packaging weighs almost 10 more, so they do weigh 19 lbs or over 9 each when split in half. the cases are very durable and heavy and should provide excellent protection for the cells, but they may be a bit much for lightweight ebike use.

as for soldering the fuse, i think they might expect that if it blows the cause needs to be investigated rather than letting a customer plug in another which could be the wrong size or do further damage even if the right size.

you have to remove a dozen screws to get to the fuse, so if it did blow it would be a real pain. i will be using the pack with a 16A controller, so i will probably use a 20 or 25A fuse between the battery and my controller, so my external fuse should blow first if there is a short somewhere.

i'm sure you know there is almost always a safety link intended to melt first in a high current battery system to protect against a total melt-down. In the a123 dewalt packs one of the interconnecting welded tabs is narrower than the rest so it will blow like a fuse there if the output is shorted. I expect that this a safety related feature that should not be circumvented.

The fuses do of course make it impossible for the cell to deliver more than 5C, so for testing or use above that level the bms must be bypassed., or the fuses changed. I do not know how this would affect the warranty.