LiFePo4 arrived

Finally got the 36V10 ah LiFePo4 battery from FalconEV.

10" L X 4" W X 4 1/2 tall

Main connectors are anderson, charger is a multipole Mil connector.
See pictures.

Have not checked it out electrically yet.

very nice, however is there no BMS?

the pack looks of good quality.

Hi

Good looking pack, what the max c rating of it though? on a lot of those packs they top out at 30A and you have a 40A controller? which will pull 40A unless you break it open and either snip a busbar or 2 off or use Richards adjustable current mod? Thanks for posting

Knoxie

I assume the mil multi pin connector is for the BMS. Nice looking connector. Is there a separate BMS floating around or just built into the charger?

It looks like the top of the whole thing was sprayed with black spray paint?

Looks like you're almost ready for a test ride...

Just received mine yesterday as well. Black paint seems to be that rubberized stuff you spray on tool handles - not certain. Initial voltage on my pack was 39.4v. Took it on a test ride today. After 9.6 miles on varied terrain the pack measured 37.7V.
The ones your showing are the 12Ah stubby prismatics I believe, not the 10Ah cells as your setup describes. There is no BMS other than a VMS in the charger. Low voltage cutoff is handled by the Clyte controller and ~ 29V. Minimum voltage for these cells according to Andy is 2.1 volts so X12 cells = 25V. They are evidently capable of 10C peak and 5C continuous.
Enjoy your pack. I only have a voltage tester so won't be able to share more specifics.

Nope, no BMS with it. Hopefully the controller handles low V cutoff.

Think the paint is to minimize shorting when wrenching. You have to dig slightly to get a connection with the multimeter.

The Mil connector is for the flinstone charger V2.

Also measured 40V with my analog multimeter.

Not planning to get into the controller. I would think the hub motor does the current drawing, not the controller. Why would a controlling device use more than the load ?

The motor draws the current, but the controller limits it.

I think you'll be fine with the stock controller.

ok no discharge bms = dangerous!

if i were u guys i'd RUN not walk and buy a couple of these:

http://endless-sphere.com/forums/viewtopic.php?t=2498&postdays=0&postorder=asc&start=60

just watching total voltage isn't enough to safely use the pack, as i've found with my pack, a single cell that is behaving eratically SHOULD be prevented from draining too low. with no BMS it won't be. - total pack voltage isn't an optimum guide for when to cut the cells off for safetey reasons!

with LiFe chemistry it's more of a Financial reason than a safety one, but with very few packs in circulation we don't know that for sure yet.

Well heck - too much Courvoisier.

I had to make the choice of whether to cancel when I found it didn't have BMS. Since it seemed like people were commenting on crappy LiFePo4 BMS in general from other sources, I took the chance to go without.

I have my 35 A fuse in line to a 40A controller. Have the cycleAnalyst to watch low battery Voltage. If I want to be careful I'll have 30V as my low limit.

When I go to 72V next spring, I'll probably get a 2nd hopped up controller, and use the 40 A as a spare.

And while riding I'll look like a Southern Redneck just carrying his tool box.

DH

Deepkimchi said:

And while riding I'll look like a Southern Redneck just carrying his tool box.

DH

Click to expand...

I was thinking of doing something quite similar, using toolboxes as pannier's, and bolting them to a rear rear with some wood and some pipe clamps - but haven't come across the right dimensions yet. My intent is to have storage on top, and the batteries (somewhat concealed) on the bottom.

I also intend to surround the battery section with spray-foam. I'll put a some small blocks on the bottom of the box, they will raise the pack off the bottom so foam can fill in. Then I'll line the box with plastic wrap, and temporarily wrap the pack in plastic wrap too. Set the pack in the toolbox, spray the foam underneath, and viola custom padding. After the foam drys, remove the blocks and fill them with more foam, cut the pack out of the saran wrap. Excess foam can be cut to the proper height.

For a lid, I plan on covering the top with more saran wrap, spraying on foam, and pressing a thin wood board on top. The foam will adhere to the wood and give a nice base for the storage section of the pannier.

With NiMh/NiCd, discharge heat made this impossible. Lithium does not generate appreciable heat during discharge, so I think this technique could be used to imbed cells into a variety of containers - one could even get creative with the center triangle...

I finished assembling my first pack from Andy's 12ah stubby prismatics last night, they are charging now, so I should have a CBA-II test on them soon.

I did use a plastic toolbox, when I was using SLA's. !
Now using a small top rack bag for the tiny LiFePO4!
Having said all that, I have been researching using Coroplast to make a tailbox for the trike. reckon it would also work to make a cheap battery compartment. The good thing about making your own, is that you can tailor make the size for your own needs. Apparently these boxes can be quite strong!

I am actually considering buying a single one of those 12ah lifepo4 from falconev to test it out. I'm really tired of running lots of little tiny cells. Price wise though they are like the same price as a123 (ah/$) but in a nice big form factor.

Freddyflatfoot said:

I did use a plastic toolbox, when I was using SLA's. !
Now using a small top rack bag for the tiny LiFePO4!
Having said all that, I have been researching using Coroplast to make a tailbox for the trike. reckon it would also work to make a cheap battery compartment. The good thing about making your own, is that you can tailor make the size for your own needs. Apparently these boxes can be quite strong!

Click to expand...

I have a plastic toolbox...well, the bottom half of it anyway. The top half is a custom lid, made on a vac former.

Took my 2nd ride - all the way to the base and back, up and down hills, the only electric bike in 50 mile radius..it goes as fast uphill as I was going before on level ground. :wink: Probably went about 2 miles - later story..

Cycleanalyst - Started out at 40.5 V ended at 39.2 V. Lowest it went was 36 V. It worried me up hills, at first it showed 30 A, later in the ride was only about 23A up hills. I must have hooked the speedometer magnet up wrong, showed 60 KM speed and total trip 123km.

Anyway, made some mods to the tool box to keep it from slipping around on the rack. Ought to patent it. Keeps it exactly lined up and same position every time.

That is an excellent solution to the battery storage problem, especially as it so easy to remove and carry indoors to your charging station, or if you need to leave the bike chained up in public.

I can't remove my batt's without a spanner and 20 minutes. So, I have a hidden cut off switch and two different types of locks to make sure nothing goes missing when I park up and go in a shop.

What is your economy like? How many Wh per mile and how does it compare to your previous battery setup?

Cheers,

Ian

And while riding I'll look like a Southern Redneck just carrying his tool box.

Click to expand...

before I went electric, my bike had a waterproof "rubbermaid" type 14 gallon storage box on top of the rear rack, tied down with a used tire tube. I needed a place to carry lunch, spare tire tube, tools, groceries, etc. Now, my Yesa battery goes inside along with the other stuff.