Mounting battery boxes

It has been a long pause again in my blog - again. The main reason is that blog update stands not on the top of my priorities list among family, main job, and actually working on HR-EV. I reckon if I would have worked normal working hours it would have taken me around 4 months. But now we are approaching 2nd anniversary of the project. Anyway, it's good that it is moving.

This time I want to show the mounting of battery boxes. Apologies for bad quality photos taken from my mobile because camera died when I needed it and I've been to busy to look for another camera.
The battery boxes are mounted on two 20x20x3 stainless steel angles: one in front bottom and one in rear top.

I used most of the car's stock bolt places on the chassis to fasten front rail using just one additional which was welded in. Rear rail was fastened to bottom sheet of the car where the spare tire is placed.
Here is the picture of one box mounted on the rails.

As you may possibly see the front rail is basically hanging on 4 20x3mm stainless steel bars bolted on top to chassis and bent around the angle bar at the bottom and welded to it. This construction allows the angle to swing a bit which is good as you don't have to be dead precise when making these rails. Being very precise in garage conditions is quite difficult. Lateral stability of this bar is achieved by the fact that boxes are bolted to it and boxes themselves are fastened at rear. The other stability element is the 0.8mm steel cover which is bolted to car and to small legs which were formed from the 20x3 bars bent around the angle ( you can see these three legs on the photo above).
Here is the picture showing the rear of the box and I hope you can see the angle bar in dark top left corner of the photo.

Here is the view from inside the car's trunk where the spare wheel is placed.

You can see 4 bolts caps in a row. That's how the rear bar is attached. Simple, isn't it? Well there are 2 additional long bolts on both sides securing the very ends of the rear rail angle. These are not visible on this photo.
On the above photo there are 4 cut opening providing access to boxes terminals to interconnect them together. You can see couple of LEDs lit up on the left which were shot when BCMS was scanning the cells.

Below are couple of very crappy photos which taken with the same mobile camera. The sad fact for the hobby project is that it is rarely possible to work in daylight as in winter night is starting early and job is usually done after main work. I will re-take with proper camera and place here. I promise :)
Here is the view from front left with all battery boxes in place. You can see the thick cable running prepared to be connected.

Here is dark view from the back bottom view of the batteries (that's how you define darkness :)

Here is the dark view of the batteries on the front rail when viewed from the car front.

Here should be photo of the boxes with protective steel sheet installed but I was too tired to remember to take a picture with it. Next time, when I bring the car on the lift again.

Batteries are home!

Long waiting is over - batteries arrived to where they belong :) I've received 45 TS-LFP90AHA batteries for my HR-EV after more than two months waiting. They've been sailing from Shenzhen in China to Hamburg in Germany and then to Klaipeda in Lithuania - a long trip.

I've taken them from warehouse after customs clearance in my trusty Subaru.

Shortly after I've opened the boxes to see what's inside. I found nicely printed manual and quality certificate. Quality certificate has lots of useful information in Chinese :) User nice manual was the same as pdf available from ThunderSky site. Beneath white cover I found a surprise - batteries :).

Here's a video shot from breathtaking moment :-D


The look at the battery itself.

All the batteries read voltage of 3.30V or 3.31V - GOOD!

The road to the future :)

While I was waiting for the batteries I've been working a lot on BCMS prototype electronics and programming. Here's a brief update about the progress:
- RealTime OS launched on ATmega640
- Serial communications programming wired and programmed - talking to PC now
- Connected to battery modules (at bottom) via opto-coupled serial port and launched battery voltages reading for BMS operation. It ballances Lithium Polymer cells within 0.02V of each other.
- Wired and programmed MLX90215 sensor (small board assembled on the left) so I can measure current of up to 10 Amps to test the concept. The finished sensor will be able to measure up to 700A from batteries and to the motor.
- Wired a contactor control circuit (simple IRL3705 MOSFET switch) and programmed its control
- Wired and programmed 12V line voltage measurement using mega's ADC
- Wired and programmed DS18B20 sensors for BCMS, Controller, Motor, Outside, Inside and Batteries temperature sensing.
- Started wiring a slot for SD/MMC card where the HR-EV's parameters log would be stored
- Some small stuff...


There are many things left to do on electronics until I start the first test of the car:
- Finalize battery module schematics, programming and PCB design, try final prototype on real battery and then order parts and PCBs
- Make schematics/wiring and programming of opto-isolated battery voltage measurement
- Make motor RPM sensor using MLX90217, wire it and program RPM calculation
- Wire gearbox speed sensor and program the speed calculation
- Make throttle sensing and control schematic and programming
- Wire digital inputs like key switch, charger on, throttle idle, gearbox neutral etc.
- Program the safety and control. Basically it should shut off main contactor if any important parameter goes critically off.

Well, there is much much more. One thing - I still haven't got the charger. In the beginning I thought about Zivan NG3 but now I'm not so sure. Still have to decide... and order it.

Of course there are lots of mechanics works to do as well. I'll update as I progress.

Motor arrived and works started, BMS prototype in progress

My Warp 9 motor arrived in November - heavy beast. I've taken the ICE out from Honda. The gearbox and Warp9 were taken to metal workshop to produce the adapter plate with perfect center alignment. Adapter plate will be produced from 12mm aluminum sheet with the 30mm spacer for the motor flange. No clutch. Shaft adapter will be done from original clutch disk part bolted on steel disk mounted on Warp9 shaft.

As told earlier I will make my own integrated Battery management and Car management system with instruments. So far made following progress on it:

• Battery Module prototype made and programmed.Tests ongoing on model Lithium Polymer batteries. It is nicely balancing the 3-cell pack controlled by PC software via serial link. One module schematic is shown here:It is derived from a nice project being developed by Peter Perkins at http://www.batteryvehiclesociety.org.uk/forums/viewtopic.php?t=1245 .
  
• Once I finish testing I'll design and order PCBs along with all electronic parts needed for them.

• Master module prototyping started with real-time OS launched. Comms and several sensors tested. The core system will be based on ATmega 640 microcontroller. Interface will be provided on Pocket PC display running the GUI software which communicates to master module and displays graphical result. The screen will be integrated in the dashboard to blend into interior design.
• Ordered more sensors chips to have various measurement inputs.

45 TS 90AH batteries were ordered and sailing to me.

Equipment arrived since last post:
Motor: NetGain Warp 9
BMS: various chips and sensors

Ordered:
Batteries: 45 Thundersky 90Ah LiFePO4s
Vacuum pump: Mes-Dea ( haven't arrive yet)
BCMS: various sensors

Need to decide and order:
Battery charger: haven't decided yet
BCMS: haven't decided which cheap Pocket PC to take as a basis for dashboard screen
Power steering: would like to find an electric steering actuator similar to used in MGs

Work done:
ICE taken out. Warp9 adapter plate started. BMS battery module schematics design and programming almost finished. BCMS design guidelines decided. BCMS master module prototype started. Simple PC software for managing batteries made.

To-Do list: (Long... but main things are generaly listed in no particular order. Later smaller subtasks would be put in detail)

• Install the gearbox and motor when adapter plate finished
  
• Make battery boxes once batteries arrive
• Design the platform for controller and electronics installation
• Decide about charger ( might design my own 2kW charger...)
  
• Finish BMS battery modules design and order PCBs and components, build the modules
  
• Make a BCMS master prototype to perform basic functions to make a first drive-test safe for me and for equipment
• Design and laydown all the power and signaling cabling in the car
• Make a dashboard design change to integrate the BCMS Pocket PC screen
• Develop a software for Pocket PC to indicate main parameters
• Build a cabin heater
• Build power brakes system
• Decide upon and build a power steering system
  

Starting my HR-V to HR-EV conversion blog

This is my first entry to log my experiences on conversion of Honda HR-V to electric vehicle. I've decided to do it since my current Subaru is quite old and I want my next car to be electric. There are no affordable electric cars available yet so I've decided to do my own conversion in similar way as many people around the world already done. In the beginning I estimated this conversion to take about 3 months but now I see it would take much longer since I decided to take more expensive components than initially thought and that makes funding the project stretched longer in time.

It is nice golden yellow 3-door 4WD SUV

I like the look from the back too

The hood opened before starting to take all unneeded mechanical parts

At this moment I have following components:
Donor car: Honda HR-V '99 4WD
Controller: Kelly KDH16501
DC-DC converter: Kelly 144V to 13.8V, 25A
Throttle: Kelly hall throttle pedal 0-5V
Contactors: Kelly 400A
Shunt: 500A 50mV
Instrument: Westach ammeter


Ordered:
Motor: NetGain Warp 9
Vacuum pump: Mes-Dea

Need to decide and order:
Batteries: most likely TS LiFePO4
Battery charger: haven't decided
BMS: will make my own...
Car management system / instruments: will make my own integrated to BMS...

Work done:
Not much yet. Bought the donor car, started stripping it down, bought some components. More information on progress should come in next posts as I make bigger steps.