Electric Bikes - LifePO4

I wanted to know what u guys think of this:

From yesa battery
The price includes the battery pack ,charger and BMS

36V 12AH LiFePO4 = USD498 plus shipping
or
36V 10AH LiFePO4 modulate the 10AH pack's BMS so that can fit your 500W motor = $507 shipped

I have put in a phone call to Fox Batteries but at this time i still haven't recieved a call back.

What is your opinion on these 2 battery setups? Modulate the BMS? 10AH or 12AH?
thx jim.....

I bought a Yesa 24V10Ah battery and I think it's great. it is rated as a 1.0C (~240W) battery but it works fine with my 500W motor. I'm told the BMS limits the maximum current to 20A, ~480W. It works fine at that level.

On their website Yesa is advertising their 36V10Ah and 36V12Ah as "standard discharging 2.0C" or about 720W. Yesa's BMS setups limit the discharge-current but I doubt either of the 36V packs have a BMS that will limit your power if you are using a 36V/500W motor and controller (which are probably designed for about 700W or 900W peak power, 500W continuous). The BMS limit may actually be 2.0C for a "standard discharging 2.0C" pack but I would have guessed it's 2.5C or higher, and 2.5C (which for one pack would be ~900W and the other, ~1000W) will provide more than enough maximum power for a 500W motor.

"By modulating the BMS" I assume they mean simply installing a more relaxed BMS amperage limit so that the maximum peak output (in watts or amps) is higher, but that seems unnecessary for a 500W motor with a battery capable of at least 720W discharge.

If the price sounds good to you, go ahead and get a Yesa battery. From my experience, the quality is good and there are no unpleasant surprises about what the battery will be like.

They do seem to have raised their prices a bit since I bought my battery, and if you want something cheaper you could check out the NiCad or NiMH packs available from http://www.ebikes.ca .

In regards to Foxx Batteries, I was able to get in touch with them by phone. They also seem to have raised prices recently, and when I was in touch with them they were out of stock for a couple weeks (and it seems they may have been out of stock during the weeks before and after the couple weeks I was trying to get them to send me a battery as well.)

If you want a straight answer about whether they have batteries in stock which they can send you, try going to http://www.atenenergy.biz/ and calling the phone number listed for Jeanne at the bottom of the page. She doesn't always pick up but in my experience she responds to voicemails.

The NiMH batteries from ebikes.ca are good, but they've also got a lower than average C-rate, and won't provide adequate output for some systems. Its worth mentioning that they also carry lithium packs as well, they're just not on the website as of yet.

I've got the 36v 12ah pack. I would definitely get this pack again. There are a few points though.

1. You have to box the bms board.
2. order a single cell charger from YESA while you're at it because the packs can go out of balance. (its $12.95USD extra)

Thx, i wall send them an email to quote me everything out the door with the 12AH.

I've called and emailed Fox and still no reply, i don't think with that type of service i'm getting just to purchase something i would like to deal with them for service.

jim....

Kats,
Just got the Phoenix Racer on a 700C front wheel, 4840 controller and the Eonyx EV 48 volt LiFePO4 Battery. Installed on an old Ross cross bike. Does about 35mph flat out, but I think I smoked the controller last night - Check this:
I Did my 44 mile round trip commute to work yesterday. Snow on the ground, about 20F when I started, battery died at about 12 miles because I had not charged it enough. Charged it at work but still not enought, died about 1/2 way home. Unplugged the front motor to make it spin easily and peadled the rest of the way home.

When I got home I was checking voltages and the controller started to smoke, that burning electrical smell many of us know. Probably killed it somehow, maybe some melting snow got in it. Waiting to hear back form e-rider with good replacement warranty news.

Will keep you updated.

The price includes the battery pack ,charger and BMS

36V 12AH LiFePO4 = USD498 plus shipping

I would consider selling my battery at $425 plus shipping from Canada. it is a 36v 12ah with 4 cycles on it. I bought a 15AH lifepo4 and use that more. The pack is great and the only reason I would sell it is because I have more batteries than I need. Let me know!

Well I had to replace the 4840 controller because most likely snow melt (water) got into it and burned up a resistor. The tech on the phone said a capcitor but the board location was a resistor.

Anyway, on to the next adventure:

The BMS board burned up while riding it this weekend 1-20-08. See enclosed photos (how do I paste in a photo?)The transistors are from the top left corner of the board when looking down on it.

I took it for a ride this weekend in about 32F weather, got about 26 miles before the battery shutdown. I pedal as much as I can to help the battery life. When the battery cut out I was only 1/2 mile from home and shut it down and pedaled home. The voltage on the battery was about 35.

I plugged it into the charger and the green light stayed on. I figured maybe it was letting the battery cool down first before charging. About 3 hrs later I checked it and the green light on the charger was still on and I smelled that burning electrical smell. Inside the battery case 2 transistors had burned off the board and were in the bottom of the case.

This should be covered under the warranty, waiting to hear back.

Hope others are having better luck with LiFePO4 batteries.

ya there lipo looks to be good quality. im shoping for lipo and i have run into there website a few times. i love the size of each cell on there packs.

im stuck between.

pingping

yesa

or this one but the only problem is thay only have the unstable packs in stock->http://66.216.110.131/product_p/37v-lithium-polymer-10.5ah.htm

http://66.216.110.131/product_p/48v-lithium-polymer-10.5ah.htm

cheers

The price includes the battery pack ,charger and BMS

36V 12AH LiFePO4 = USD498 plus shipping

I would consider selling my battery at $425 plus shipping from Canada. it is a 36v 12ah with 4 cycles on it. I bought a 15AH lifepo4 and use that more. The pack is great and the only reason I would sell it is because I have more batteries than I need. Let me know!

well if your looking to sell im looking to buy. if still interested email at collegecourt626@yahoo.ca
and we can work somthing out.

cheers

skip it i got a deal $415.00 shipped 48v 10ah lifepo4 !!sweet!!

I am interested in one of those battery packs for my 100 watt headlight. The problem might be the BMS. The PAR 36 bulb may run at 8-9 amps at 12 volts but will suck down several times that current for a split second while the filament warms up. Would this slag down their circuits? Or can I just get a beefier BMS? The SLA I use now is about 12 pounds and lasts only one hour.

not sure when i get my pack ill run some tests on the bms see how fast it cuts out. :)

Karma, where did u final decide to get one at?

pinping

this is a interesting thread on the endless-sphere forum about pings cells, one guy had his bms fail.

http://endless-sphere.com/forums/viewtopic.php?f=14&t=2931

when i get mine i may add a low profile heatzinc.

cheers

well my lipo is finally on its way. i was thinking on using this case-> http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=698875&CatId=514
to protect it. its small but theres other sizes.

this one should do it :) http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=1225171&CatId=514

Karma, i like that it floats in salt water!
As i stated prior, my ping pack is installed in a hard liner canvas lunch box. There is one concern that i have; after running it hard for 13 miles or so the pack is quite warm. When the weather isn't threating i leave the top of the box unzipped for air circulation. But most of the time i have my big book bag bungeed on top of it so that defeats my purpose.

So i wonder what the temps would be like inside of that sealed camera box?

I just think that "heat" is bad, maybe i'm just paranoid.

jim.....

hmm ok ill do some tests on the bench with some high watt bulbs to see how hot it gets, that could be a problem come summer.


i could allways make my own case that Cools the cells.->http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=3516740&CatId=3486


lifepo4 sandwich :)



cheers

heh ok its a little smaller than the pic on ebay but i guese pictures puts on 10 pounds. no problem ill just think smaller :)

cheers

lol aparanty not everyone likes the ev battery look. o well i love it and it will last the full 1000 charges.
i found a few more duck tape batterys on the net that shorted do to pulled wires and shorted bms,s.
in the long run and the heat of summer that ducktape will get soft and melt. so i changed my mind and
made my own case, its not finished yet.

and no its not my coffee table, or my fish tank lol. wow a amazing side effect i can now mount it anyware ;)


cheers

its finished im going for a ride.

cheers

Karma that picture looks like a Golden Motor? I was just wondering how fast that will make your bike go? I am wanting to put one on a recumbent. Would you buy it again our would you go with another brand? Thanks

yup im bulding another for my kid, i get around 35mph even faster if the winds on my back or im going down hill.
ohh sorry i have been told im building two more :) heh.
my main server is down when i get it fixed this week i can post a few link for deals.

cheers

Karma,
I have 2 questions:

1. Did u do any type of testing with your Ping batteries? My only testing is charging it up and riding, so some of your technical data would be nice.

2. With regards to your vids with the controller mods. My controller was missing the heat sync paste, but i ran into a problem to remove the R11 resistor for low voltage. On the controller that says "R11" i don't see a resistor, it just looks like a solder trace. So i was afraid that i would not be able to repair it if it was not done correctly. I couldn't tell by the vid if i was correct or not. Any ideas?

thx jim....

This is mostly repeated info from the earlier thread, I'm attaching two images here. The first shows the whole board, the second is a close up of the three resistors. (This site only allows 128kb images.) The green arrow points to R73, red to R4, blue to R11. The cutoff voltage is:
3.1 * (R73 + R4 + R11)/R11
From the factory, the values are: R73=11000, R4=0, R11=1200 for a cutoff of 31.5V
The cutoff gets triggered when the connection between R4 and R11 reaches 3.1V.
To increase the cutoff voltage you can increase R73 or R4, or decrease R11
To decrease the cutoff voltage you can decrease R73 or increase R11 (R4 is already at zero)

Thanks to djimme for letting me know that this thread was here. I've pretty much put my bike away for the season now since the temperature got down below freezing in the mornings so I haven't been checking in on this forum much.

Have fun,

Pete

http://goldenmotor.com/SMF/index.php?topic=198.0

hope this helps

cheers