Yet another Yellow Ninja 250 Conversion!

[bquick]

Here's my battery holder. On the bottom is one battery laid flat. On top of that are two batteries right side up. On top of those are two batteries up-side-down. This minimizes the overall height. The final battery is on the front. Unfortunately, I didn't take into account that the front tire moves with the suspension, so the tire hits the front battery when I use the front brake. Tomorrow, I'll move that battery up as far as possible.

batteries1.jpg (64.96 KiB) Viewed 1238 times

batteries2.jpg (59.55 KiB) Viewed 1238 times

batteries3.jpg (64.33 KiB) Viewed 1238 times

[pgt400]

Very nice fab work on the battery tray! As long as you charge them after each use the AGM's are near bullet proof with zero maintance. I have over 1000 miles now and have noticed no change in performance. I changed my on board chargers to 5 amp units so I can charge fully in about 4 hours and oppurtunity charge any time. My ride to work is 7 miles each way, I use about 9ah and charge at work. Yeah, you probably doubled the weight of batterys (although you have more voltage now). I bought 4 of the newer blue headway cells to play around with and considered ordering 100 but I want to wait and see how they fare in motorcycle applications. There was a group buy that Travis did and several are going to use the in motorcycles.

As far as performance how would you compare the older headways to the agms? I'm wondering how the voltage sag or current delivering capibility effect acceleration?

[pgt400]

Brad, as I hit send I relized you mounted the top batteries upside down. I've read on several sites that AGM's can be mounted on thier sides but should not be mounted upside down. If you didn't already, you may want to check with B&B.

[bquick]

Phil,

I double checked the data sheet and it says,

"The battery is constructed by plates,
separators, safety valves and container.
Since the electrolyte is held by a glass-
mat separator and plates, the battery
can be used in any direction and position
without leakage."

As far as performance goes, my acceleration is a little slower now than it was, but not by much. It's probably mostly due to the extra weight I'm carrying. I went from 64 volts to 72 volts. I had to change from a 15 tooth sprocket all the way down to an 11 tooth, but I may go back up to 12. The bike is much heavier now, but still handles well (gotta love these little Ninjas). The fun factor is about the same.

I like the simplicity of having a simple volt meter on the dash to act as a fuel gage. I went for a 16.3 mile ride today. Top speed only drops from 48 mph to 45 mph after 16 miles. With the Headways, top speed didn't drop until a cell failed!

For me, the simplicity and peace of mind is worth having the extra weight and shorter range. As long as you get the range you need, I wouldn't switch batteries yet, unless you want the challenge of keeping them working. I figure if I can get three years out of the AGM's, maybe I can put an Eestor power cell in and get some REAL performance!

I like pushing the envelope, but after spending $1900 on batteries, building a pack, having a few cells fail, replacing them, then having more cells fail, replacing them with A123's and having more cells fail, I was done pushing. I'll stick to using my A123's in my model airplanes.

After my experience with the Headways, I was giving up on the idea of doing a car, but the simplicity of the AGM's has me thinking about it again.

At your suggestion, I lowered the regen, but It would only let me go as low as 50%.

I wonder if we are using the same chargers. I got mine off ebay. Like you, I have three of them, each charging two batteries. If I remember correctly, they put out 6 amps. I have mine mounted in the tank (I cut the bottom out). The tank gets warm as it charges.

Thanks again for the help.

- Brad

[pgt400]

I hear you, 2k for batterys only to see them die off has to suck. I almost bought cells from Victoria a couple times but finally decided to kill the AGM's first. The first 5-6 times I charged I checked the cell voltages...they were always dead on. Be prepared for a big performance drop below 60 degrees. Mine seems stronger after my second charge during the day, right off the charger (as opposed to sitting charged overnight). I also checked the BB site, it stated "do not reccomend mounting upside down" This was for the EVP-35 ???

[Jay64]

on the agm mounting, I had read once that they can be mounted theoretically in any position, but since there isn't much difference between the dimensions of mounting a batt straight up and straight down, don't mount it upside down just to be on the safe side.

[pgt400]

It was not so much a spilling problem, it was charging upside down that is not advised. Attached from BB battery site.

bb battery.JPG

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[bquick]

I looked again at the data sheet for the EVP35-12, and it doesn't include the statement about mounting them inverted. Maybe that's only on the -12H?

- Brad

[pgt400]

I looked again at the data sheet for the EVP35-12, and it doesn't include the statement about mounting them inverted. Maybe that's only on the -12H?

- Brad

Brad, did you check the BB site? http://www.bb-battery.com/productsevp.asp It says this for all the EVP-35AH I have noticed that some reseller sites do not mention this. Looks like BB added it in?

Phil

[pgt400]

Picked up 24, 40ah Calb prismatics for the Ninja. The AGM's are still going strong at 2,600 miles...thought they would have died by now. The Lifepo4's will shave off 70lbs and increase my range. Started welding up the frame yesterday. Ordered (3) Cell-logs for BMS.

24 calb 40ah.JPG (30.29 KiB) Viewed 659 times

[Doctorbass]

Nice!

How many C rate they can take on discharge?

I was close to buy some like those for my e-trike

Doc

[pgt400]

4C for 30 seconds as spec'ed. Originally I was going to use Headways but didn't want to contend with a 96 cell pack, this and my riding is 1.5-2C normal, 5C for a couple seconds of accelleration. The Calb cells have gotten good reviews for quality on other sites....I measured 48AH at 30 amps (.1 ohm resistive load). I have 3 Cell-logs for the BMS....but may use the Mini-BMS system have not decided yet. BTW I am still using the A123's you provided to me, 16S3P pack with V2.5 Signalab. I have about 80 cycles on them with no problems.

[Gordo]

Nice!

How many C rate they can take on discharge?

I was close to buy some like those for my e-trike

Doc

Doc;
The TS Cells are available here on the west coast. My last 3 were $53 Canadian, landed at my door. You will have shipping and your tax.
2C continuous is OK on them. I have 20 in my scooter, with 3 lazy ones, hence the new 3. I have a BMS on the way that I am going to try before I replace the 3.

[pgt400]

I've got about 70 cycles on the 24, Calb 40ah cells using the mini-bms system. So far very happy with both the cells and the mini-bms. Truely a plug in and forget system. All the cells have remained balanced....they seem to reach their 3.65 volt peak within a few minutes of each other.

[grindz145]

Sweet! How many miles do you have on total? I'm wondering what brush life will be like?