TexasElectric - eBike build

[California98Civic]

Hey, I noticed this thread back when it started but was too busy to participate. Then I forgot. Now I noticed again. I opted for LiFePO too. But I bought my pack.

Great look you are achieving. I will continue reading through the thread. I love the mounting bolts for the box-to-frame connections. Wide and flush with the inside of the box itself. Nice work. Mine is more of a crude affair. I was planning a full triangle box, but I lost my nerve at dismantling the battery I bought in order to re-position it. That will be for another day, another revision of my bike someday.

[TexasElectric]

California98Civic
I am glad you were able to find this thread again. Did you document your eBike build online (if so, do you have a link)?



Some of you guys expressed interest in the cells I am using. Here is a link to a forum where people smarter than me (and who have the right tools) have tested hundreds of these LiFePo4 Tenergy 32650 cells. The consensus is that they are achieving 90%~ of the stated capacity. Not too bad in my opinion. The biggest reason for this (as mentioned in the forum) is suggested to be because the cells have been sitting in a warehouse for the past 3-4 years.

Anyone familiar with LFR/Tenergy LiFePO4 32650 5500mAh 3.2V Rechargeable Batteries?

[California98Civic]

Originally Posted by TexasElectric

California98Civic
I am glad you were able to find this thread again. Did you document your eBike build online (if so, do you have a link)?

...

I do have a thread. Here it is at the last update: http://ecomodder.com/forum/showthrea...tml#post542573

Whenever it becomes necessary to replace this battery, I'd like to be able to replace it by "making" a battery myself something like what you are doing. I have much to learn/practice before I get there.

[TexasElectric]

Well neat-o, I just finished my first test ride on the eBike! (about 1/4 of a mile up/down the street).

I worked hard to finish up the battery 'packs'. I had a little bit of touch-up soldering to do.

I took it very easy going up and down the street, I didn't want to stress anything.

Where I stand right now...
- I need to install the torque arms.
- I am waiting for more heat shrink to arrive on Monday (for the battery 'packs').
- I need to order some small heat shrink tubing for cable connections.
- I need to incorporate the BMS into the system.
- I will place an order for an charger/battery plug/connector this evening.
- As soon as I post this I will cut out a new right side battery box panel (because I glued the interior foam to the outside of the one I had). I will also prime, paint and cut out/glue a new piece of foam to the new battery box panel.

Once I get the battery box and the batteries associated connections squared away and finalized I'll start doing longer tests .

https://www.youtube.com/watch?v=--LLQfcO8II

[California98Civic]

So you are running 48v and how many amp hours now? What range are you now expecting? 75lbs seems so heavy!

[TexasElectric]

California98Civic

yup, 48v system (just over 53 volts fully charged). After doing some research/reading online (based of other peoples tests/experience with the cells I bought), I am estimating to have a total amp hours of 26ah-27ah. As for range, dont know yet, I will need to run tests. I am hoping (as per the math) to have a range of 80 miles at 20mph average, and 50 miles at 30mph average.

6/19 update

I'm being lazy today...

I cut out a new side panel for the battery box, tinned the 16 BMS leads (orange color), tinned 8 cables that will connect to the 8 battery 'packs' in the battery box (red color). I also finished applying heat shrink to the remaining 'packs'.

I am still working on a ventilation system for the battery box, (i'm thinking ram air style system)

Lastly, I will probably throw in a few desiccants into the battery box and rear bag to help keep any moisture under control.

[California98Civic]

I only drain my battery pack (14ahr) halfway generally, as a strategy to extend its life. I get 12 miles on half the charge, with heavy use of the motor and lots of hills. Over 3000 miles total on the bike now. I used ebikes.ca calculator to do the range and speed estimates, but I also bought their hardware so the estimates might be more accurate than if you pug in details from your set-up. I think only experience will tell you for sure what you have in terms of range and speed. Looking good!

[TexasElectric]

California98Civic

3000 Miles! holy cow...


6/20 update

Still kind of a lazy day... I tried positioning the battery 'packs' in multiple configurations. I decided to cut off the black heat shrink and make one BIG pack instead.

I wasn't having too much luck de-soldering the negative leads, so I cut most of them.










It fits!

[TexasElectric]

6/21 update

I started working on the torque arms. I was only able to find one position for the right side that worked best for mounting the torque arm. I'm still working on the left side, (i've got a brake caliper and rear rack mount to deal with). I'm using 5/8 inch rubber lined clamps to secure the other end of the torque arm to the frame.

I also cut out two 7mm EVA foam pieces to put above and below the battery. I'll finish the battery tomorrow and heat shrink it.

This weekend I am planning to do low speed tests, (15, 20, 25mph). I'll ride for 10~ miles and monitor the average watts. This should help me estimate my range.

[California98Civic]

Originally Posted by TexasElectric

California98Civic

3000 Miles! holy cow...

The key is I built the ideal range for all my most common trips in my immediate area. I ride instead of drive frequently, and that way the miles pile up somewhat quickly (when it is road worthy at all). It is not a pleasure bike, though it is a pleasure to ride. It's a worker.