LifeBatt cells now available for ebike use

[Arbiker501]

Yeah Don,

I would need that. I mean nothing says high end product like duct tape .... that was a good one.

 

[GGoodrum]

I finally got around to finishing up both 12-cell packs:

I'm off to do a test ride now...

 

[Battboy]

Hey Gary - You crazy Aerospace Engineer! Happy New Year, and please give us a Ride Report if you don't do a face-plant first

 

[green hornet]

Got a price on these packs ?
when available ?

 

[Battboy]

These packs are available NOW. Gary can give you pricing IF he makes it back from his "Rocket Run" ?????

 

[GGoodrum]

I had to do some rewiring on one of my bikes, so I didn't get to do a test ride today, but it is first on my New Year's todo list.

The 12-cell and 16-cell versions will both be available starting Wednesday. I will post a link here to the website page for ordering.

Both will come fully assembled and tested, and will have LVC boards pre-installed. RC-styled balancer plugs will also be provided. The price for the 12-cell 40V/10Ah pack will be $675, and the 16-cell 52V/10Ah version will go for $850.

I'll have more info in the next couple of days.

-- Gary

 

[green hornet]

Does this price include charger ?
what kind / name ?
what amp ?
If not what price ?

 

[efreak]

Thanks Gary,

I hope all is well, in answer to green's question I am pretty sure those are the assembled cells and lvc only price charger is extra, as they were like $ 50 per cell raw.

efreak

 

[cnb]

how fast could you charge these lifebatt's? what charger do you use? (compared to regular lipos, these seem about double the weight in getting the same voltage/ah)

Gary, you sure you don't want to make some profit on building dewalt packs? they'd take pretty fast to build, you could divide them in 10-20 minute intervals over a day or few days. you've already provided lotsa good info on these dewalts, least I could do is buy something from you. Or if not, could you write a quick summary on assembling your 10s2p packs?

(such as how interconnecting PC boards, balancer plugs, power leads, harness, G10 end plates, jumper plug, deans, will go)

 

[deecanio]

wow,

amazing work guys, with these packs and bobs modded xlyte controllers these would be the best combination i've seen so far.
Great effort and best of luck with the venture!!


cheers

D

 

[green hornet]

I ask again -
charger included or extra ?
36V LiFeBATT Charger with automatic cut-off protection = $ 175.00 USD + Shipping

Is this correct ?

 

[Battboy]

NOT CORRECT: The 36V Charger on the LiFeBATT website needs to be removed. The 36V packs Bob & Gary are doing will have a Charger that is designed specifically for their pack arrays, and it will be required to enforce the 2 Year Warranty that LiFeBATT is offering with these packs. Sorry for the confusion folks! Not sure what the price will be yet?

Don Harmon

 

[GGoodrum]

That is correct, the pack prices include the LVC protection boards, but not the charger. Bob and I are taking a two-pronged approach in regards to chargers for these. What we will have first is a new "Charger Management System" (CMS) board that will connect into a special multi-wire harness with heavy duty Molex connectors. The other end of the CMS will plug into any number of existing 36V and/or 48V CC/CV chargers, like the Soneil 4-5A models that are used with many existing setups. The CMS will ensure that each cell gets a full charge. This we feel is the most cost-effective way to be able to offer a LiFeBatt-approved charging/balancing solution, without having to resort to a messy and overly complex VMS/BMS board that would have to be pack-resident. Of the three typical BMS functions, LVC protection, over-current protection and balanced charging, only LVC protection needs to be pack-resident. The controller already handles current limiting, and that just leaves the balanced charging issue, which can be moved to a separate CMS board.

In addition to the low-cost CMS approach, Bob and I are also going to do a completely new charger that Bob is designing that will connect into the same Molex pack connector, and individually charge each cell at a full 1C/10A rate, which means a fully depleted pack can be recharged in about an hour. We plan on having both 36V and 48V versions of this new higher-power design. These won't be available until sometime this spring, however.

I was going to start offering the 36V and 48V packs starting tomorrow, but I have decided to wait until the CMS boards are ready, which might not be for another couple weeks. If somebody doesn't want to wait, PM or email me (ggoodrum@tppacks.com), and I can do versions with RC balancer plugs that can be used with existing RC balancers, like the Hyperion LBA10, or the ThunderPower TP-210V. When the CMS is ready, it can be fitted with matching balancer plugs.

My bike wiring issues have now been sorted out, so I haope to have my first ride report later tonight.

-- Gary

 

[GGoodrum]

I finally got my first test ride with these in late yesterday afternoon. Bottomline is that I couldn't really tell the difference between this 24s 80V/10Ah LiFeBatt setup, and the 24s6p 80V/13.8Ah a123 setup that is usually on this bike. It feels exactly the same, which is good news. I really gave this about as hard a test as I could, which is multiple dead stops going up hills. I pretty much just maxed out the throttle as much as possible.

Here's what the setup looks like:

I didn't do anything to tidy up the wires, etc., as this bike normally has the a123 setup. These packs are going on my wife's new Townie, which I hope to finish up today.

As I said, I did my best to "work" the packs. I hit multiple 76-77A/4500W peaks and had lots where I just kept the load on for as long as possible. Some were long enough that the current dropped to about 50A and the voltage dipped to about 32.5V per pack, which is about 2.7V per cell. I've done similar tests with the a123 setup on this bike, and the voltage dipped to about 2.8V per cell for the same sort of long full throttle climbs up a hill. This is exactly what I'd expect, given that the a123 cells have a bit higher "C" rating, and that the 6p a123 setup is 13.8Ah vs 10Ah for the LiFeBatt cells.

Here's some shots of the two WattsUp readings:

As you can see, I went a total of 5.5 miles and the "burn" rate is close to 1Ah/mile, which shows how hard I pushed these. My normal usage rate is about 600 mAh/mile, on a normal ride through the hilly terrain around here. I was going to try and do a video yesterday, but i was losing light, and didn't have time to rig the camera/unipod. For the next ride, I'll do this for sure.

All-in-all, I'm quite pleased. I was hoping that they would have similar performance to my proven a123 setups, and I was not disappointed. I'd put these up agianst any of the Chinese LiFePO4 imports any day, even those with higher capacities. That's the rub with most of these, you have to use cells that have large capacities, like 20Ah, in order to keep the voltage drop under load from killing the cells in higher powered setups like i'm using, which can see 4500-5500W/75-85A peaks.

More later...

-- Gary

 

[Ypedal]

Daaaaamn that's cool ! Thanks G !

In comparison.. my GEBattery ie: Cheer-Ocean foil pouch 24ah ( 2 x 12ah paralell ) fell to 2v per cell at 35 amps instantly ( a 44v pack dips to the controller's cutoff of 29v and the controller rolls back the amps ) , forget long hills..

I'm waiting for my replacement packs in prismatic metal cans.. will be interesting to compare results !

Keep the info comming ! THANKS !

edit : 1ah per MILE !!! sweet lord man.... i get something like 15wh per km lol...

 

[GGoodrum]

1ah per MILE !!! sweet lord man.... i get something like 15wh per km lol...

On one pack I used 169Wh and the other 161.5Wh, so 330.5Wh total. That's about 60Wh/mile, which is really high. My normal Wh/mile rate is usually down in the mid-30s. Again, the purpose was to do a bit of a worst-case torture test, which these packs passed with flying colors.

-- Gary

 

[disndat]

Hey Gary just wondering how these compare weight and size to the A123 13ah packs?

Thanks

 

[GGoodrum]

Hey Gary just wondering how these compare weight and size to the A123 13ah packs?

Thanks

Actually, they are very similar. You need four a123 cells to roughly equal one of these (2.3Ah x 4 = 9.2Ah). With the extra interconnections and assembly bits, each a123-based pack works out to about 80 gms a cell, so a 12s4p 40V/9.2Ah a123 pack weighs about 4 kg, or about 8-1/2 pounds. The 12-cell 40V/10Ah LiFeBatt pack shown here weighs about 10-3/4 pounds, so a bit more, but it is a lot more ruggedized and plus you gt an extra Ah of capacity, compared to the 12s4p a123 pack.

I don't remember the actual size of the last 48-cell a123 pack I did, but they are roughly the same volume. the a123 packs is lower, but wider, and both are about the same length.

-- Gary

 

[monster]

i like the way you have used two watts up meters to measure you 80v because the max volts the meter can take is only 60v. i didn't think of that.

 

[Beagle123]

Hi Gary:

Are those Watts up meters connected directly into your power line without a shunt? If that's the case you may be adding some resistance to your system. I beleive that the Watts-up meter uses 12 guage wire. If you use this calculator:

http://www.stealth316.com/2-wire-resistance.htm

it shows that you'll get a voltage drop of 1.5v with only 12 feet of 12 guage wire @ 80 amps (you're running a lot of power through those wires). Also, I bet the meters themselves add some resistance. You might just want to use the meters for testing then bypass them for normal use.

I'm using 10 guage wire on my bike, and it seems to be working well.

I'll give some exact numbers on my voltage sag on my build thread later.

 

[GGoodrum]

Hi Gary:

Are those Watts up meters connected directly into your power line without a shunt? If that's the case you may be adding some resistance to your system. I beleive that the Watts-up meter uses 12 guage wire. If you use this calculator:

http://www.stealth316.com/2-wire-resistance.htm

it shows that you'll get a voltage drop of 1.5v with only 12 feet of 12 guage wire @ 80 amps (you're running a lot of power through those wires). Also, I bet the meters themselves add some resistance. You might just want to use the meters for testing then bypass them for normal use.

I'm using 10 guage wire on my bike, and it seems to be working well.

I'll give some exact numbers on my voltage sag on my build thread later.

They are connected in series with 10-gauge wires, but I'm not worried about a little loss. I can still easily hit 4500-5000W/75-80A peaks.

On the rc-electronis-usa site (the Watt's Up manufacturer...), it shows a "3-wire" connection option that basically eliminates the need for a high-current positive wire connection. I am going to re-wire my setup to try this.

-- Gary

 

[Doctorbass]

Hey Gary, that's a very interesting test you did. i was wondering about weight and energy between chinesse and A123 cells..

I bet the match with a charger like teh one i'm building would be awsome!

My final calculation give me a charge current of 17A per parallel cell group for the A123 and 15 for lipo or 18650 that are 4.2V charge.

17A for a 10Ah would cahrge completly your bike in less than 40minutes !

Doc

 

[Beagle123]

They are connected in series with 10-gauge wires, but I'm not worried about a little loss. I can still easily hit 4500-5000W/75-80A peaks.

I wasn't aware that they used 10 guage. And those peaks are very impressive. If you were reaally interested, you could connect a voltmeter and test with and without the meters. I may have to get one of those Watts-up meters.

 

[Beagle123]

Our "Watt's Up" WU100 and Doc Wattson R102 meters use AWG 14 or heavier gage wire and high temperature silicone insulation.

That quote is from this page:
http://www.rc-electronics-usa.com/meter-faq.html#faq8

ARe you sure tose are 10 guage wires? Where can I get the one with 10 guage?

 

[curious]

Question for Bob and Gary on the charger - how far are you in the process of designing the new charger ? I am asking because I've started working on my own switching 1C charger along the lines of ideas that I've posted here recently. I already have it running in Spice simulator and ready to start working on a PCB. I planned on making the PCBs or even kits available at cost for the community. However if you already have something that will charge LiFePO4 cells individually at about 1C rate in more advanced stages of the development I'd rather spend my time on something else. Alternatively I can offer my help with your design. Please let me know.

Prior to discovering you plans for the dedicated charger I wanted to ask you make LVC output available on the balancing connector to avoid replicating this circuit inside the charger - my circuit uses it to reduce the charge rate until all cells are above LVC threshold. What connectors do you plan for balancing plug ?