Build Session 20 (60 mins): Started Prepping Battery Racks for Paint

Finding time to work on my truck lately still seems to be few and far between...

However, I was able to fabricate and weld in a final battery rack support member between the two forward battery racks.

I plan to epoxy coat (paint) the entire frame with POR15 rust protector and chassis coat. I'm currently prepping the frame by removing the rust, dirt, etc...

I'm pretty busy of the next few weeks but I hope to complete the prep work and rack painting by mid November.

Ordered a Zilla Z2K Controller Today!

Zilla Controller

I first discovered the Zilla controller a few years ago when I began my EV conversion research. Ever since then I have been drooling over its rich feature set and performance capabilities.

My decision to upgrade to lithium batteries (LiFePO4) has given me new reasons to pondered the idea of upgrading my 144v Curtis Controller to a Zilla controller because of it capabilities and features. Specifically I want to be able to programatically shut the controller down when any of my Thunder Sky Cells reach their minimum voltage range. This will allow me to protect the cells from under-running damage. In addition, the Zilla will allow me to run higher voltage which means better performance.

Recently I discovered that Otmar who is the founder of Cafe Electric (makers of the Zilla controller) plans to sell the Zilla rights and stop production. So I decided that I'd better buy one before they are completely unavailable and/or even more expensive. The only downside is that it will take 6 to 8 months before my controller will arrive. Once my Zilla arrives I plan to move the Curtis controller to my Porsche 914.

Hmmm.... Now I need a TransWarp 11 motor with direct drive shaft. Then I can eliminate my transmission altogether and really make this truck peppy!

Build Session 19 (180 mins): Forward Battery Rack Complete, Welding Supports

I completed the battery racks today!

Welded the six supports in place...

The completed forward battery racks...

The rear and forward battery racks...

LiFePO4 Thundersky Batteries and a PFC50B Manzanita Micro Charger

I have decided to go ahead and order 45 Thundersky Lithium Iron Phosphate (LiFePO4) Batteries. My plan was to purchase directly from Everspring.Net in China as I was unable to locate a competitive source of Thundersky cells in the U.S. until recently. However, I am currently working with Manzanita Micro and have ordered their amazing PFC50B charger, LT5B Regulators, and they are building me some custom cell under running detection hardware. In addition, they have agreed to provide me with Thundersky cells at a discount which also allows me to avoid the hassle of dealing with importing the batteries through customs.

So far, I highly recommend this company as their chargers appear to be superior to anything else that I have researched. Clarice (sales) and Stephen are extremely helpful in answering my pre-sales questions (Warning: Don't send too many questions to Rich though...he can be a bit grumpy).

Build Session 18 (180 mins): Forward Battery Rack, Fabricating Supports

Yes, I finally finished the rear battery rack and am now working to complete the forward battery rack. When complete the rack will hold 32 160ah thundersky batteries or 8 Lead Acid batteries.

First I cut the 4 lengths of 2 inch flat bar for the four U supports...

Then I bent the four pieces into U shapes using the torch and a few clamps...

The four U supports are complete. They will be welded two on each side.

Then I cut and bent the two longitudinal supports.

And thats it...in the next session I will weld them in place and finally be done with the rear battery racks!

Build Session 17 (60 mins): Rear Battery Rack Complete

Yes it's been a while since my last post. Work is extremely busy right now but I will attempt to make some amount of progress and post at least every week or two. We'll see...

This month I was able to complete the rear battery rack. I made some size modification on the original design to maximize the space for additional LiFePO4 batteries. My current plan is to purchase 45 Thundersky 160ah batteries. I will install 32 of the cells in the forward rear boxes and the remaining 13 cells in this rear box. I estimate the the rear box will hold 34 which I plan to use in the future if I add more cells for a higher voltage system.

Removing the rear cross member support...

Cross member removed...

Working on the final two rear rack supports...more bending.

I made two just like this...

And installed one on each side as depicted below...This will keep the batteries away from the rear shocks.

Lead Acid or LiFePO4 (lithium Iron Phosphate) batteries?

In a previous post I indicated that I would most likely purchase the the Trojan T-145 Deep Cycle lead acid battery http://www.trojanbattery.com/Products/T-1456V.aspx. They are supposed to be one of the best deep cycle sealed lead batteries. They are relatively cheap (approx. $3000 total for 24 batteries). Unfortunately, they are also EXTREMELY heavy weighing in around 1700 pounds. Added weight will decrease range and performance. Based on my calculations and verified by several EV'ers that I have contacted I may only see a range of 40 miles using lead acid batteries.  While this may be enough to support much of our daily driving it just doesn't feel like enough for me. Especially when you combine the fact that these lead batteries require regular maintenance (watering) and will degrade over time when not fully charged.  


There may be an alternative... Lithium Iron Phosphate batteries. This battery technology suffers from none of the pitfalls that I mentioned for lead acid batteries and contains many times the amp hour capacity. Plus lithium phosphate cells are 20% of the weight of lead acid batteries which will increase performance. 


I have been researching Lithium batteries for a couple of years and many of you may remember that Jared and I built custom A123 Lithium Nano-phosphate battery packs for our electric bicycles a couple of years ago. The batteries were extremely successful but a lot work, soldiering, etc... In addition, the A123 cells are very expensive. To achieve a range of 75 miles in my S10 EV I would need well over $20,000 worth of A123 cells that must be surface welded "soldiered" into custom packs.


Recently, however, I have rediscovered a potential alternative. Thunder Sky (http://www.thunder-sky.com/products_en.asp?fid=66&fid2=70) LFP cells. I did a little research on these cells a few years ago but found several people who were having problems with some cell batches. However, apparently, newer versions of these cells are popping up in a few Electric Vehicles around the globe and appear to be performing quite well. 
The cells are manufactured in China. I have contacted their primary distributer and it seems that I could get my hands on these 160 amp hour LiFePO4 cells for about $9,000+ shipped to nearest SEA port. I estimate about 75 to 100+ miles range for this amount. Plus no soldiering hundreds of little cells as the Thunder Sky cells are manufactured in large form factor. Just 45 cells will be tied together with bolts and electrical cable. I'm considering purchasing even higher amperage 300 amp hour cells which would cost more but could increase my range to possibly 200+ miles. Yes, I'm drooling...


Anyway, I have been reworking my battery rack design to accommodate either battery technology in case I actually get my hands on some of these cells. :)