An Easy EV Conversion Kit For People

Open Source Civic EV Kit

After spending the past year and a half converting a Porsche 914 to an electric vehicle, I decided to expand my horizons by designing an open-source electric vehicle (EV) conversion kit for a commonly used car. There are already commercially available kits with excellent, detailed instructions for how to convert a vehicle. Unfortunately, these kits are for much older vehicles like the Porsche 914 and the VW Rabbit.

2008 156

Battery Racks, Continued

Open Source Civic EV Kit

I did some more work on the battery racks over the past few days. The biggest challenge is getting everything to fit properly without hitting any blockages. At this point, I think I have all of the metal pieces cut, but I don't have the bolt holes drilled. Note: the following descriptions are a bit verbose because I'm trying to keep track of all the detailed measurements as I go. Here is a closeup of the front battery rack on the driver side.

2008 133
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Rotating the Brushes on the Warp9 Motor

Open Source Civic EV Kit

Many people don't realize that the Honda crankshaft going into the transmission actually turns clockwise for the forward direction, as opposed to counter-clockwise for the vast majority of cars. As such, most EV motors have advanced timing on the brushes to optimize counter-clockwise rotation. Since we have a Honda Civic, we're going to rotate the brushes on the Netgain Warp9 motor so that they have optimal advanced timing for the clockwise direction.

2008 130

Assembling a Price List

Open Source Civic EV Kit

I always wondered how much this kit really cost me, aside from tools, so I assembled a total parts price list and uploaded it to the Civic-EV Google Group here: [link] I'm a bit surprised I came out below $10K (barely). One of the high-wants for the kit was that it would cost Cheers, Tim

2008 100

Rear Trunk Battery Rack

Open Source Civic EV Kit

Today was busy, so you should see a few posts. This first one is all the work I did installing the rear trunk battery rack base. As I mentioned before some of this will be verbose as I'm trying not to lose all the finer details. A few posts ago, I cut some 1.5"x1.5" square tubing 18" long (1/8" wall) and drilled a 3/8" hole in each end, 5/8" from the end. After laying these down in the trunk where I wanted to put them, I realized that there is a manufacturing "bump" on either side of the trunk.

2008 126

Mounting the Batmon Boards

Open Source Civic EV Kit

These boards monitor the voltage on each battery and signal back to the charger or the controller if there is an undervoltage ( The Belktronix kit comes with a bag of tie-wrap mounting pads and instructions to cut the pads in half to hold the BatMon boards to each battery. Here are all the tie-wrap mounting pads from the kit with form-fit cut tabs, ready for BatMon installation.

2008 100

Tach Mount, Splash Guard and POR-15

Open Source Civic EV Kit

The POR-15 starter kit arrived today as well. POR-15 is really tough stuff and this $20 starter kit will have everything I need. (no, no, this isn't an ad for POR-15) For those who are curious, the starter kit contains metal cleaner, surface preparer, the POR-15 paint itself, rubber gloves and application brushes. It's still pretty cold in the garage, but I motivated myself to get out to TAP plastics (10 blocks away) and pick up some ABS plastic for the improved splash guard.

2008 100

Mounting the Zolox Sensor

Open Source Civic EV Kit

The screws that came with the mounting kit stripped out the plastic, so I sunk some depressions in the backside of the ring where the bolt holes were and put in 8-32 x 1" bolts from the backside. After futzing around awhile, I was able to get the spacer ring for the Zolox tachometer sensor to line up. Here's the bottom of the mounting ring.

2008 100

Wiring up the Vacuum Pump

Open Source Civic EV Kit

One of my goals for this kit was to utilize as much of the existing infrastructure of the car as possible in terms of fuses, relays and wires. To properly wire up the Gast vacuum pump, I wanted a fuse for safety and ideally a relay to protect the pressure switch from arcing too much. Fortunately, the Civic had the features readily available for this in the form of the radiator fan circuit. The under-hood fuse box had a fuse and relay for this.

2008 100

Installing the Potbox

Open Source Civic EV Kit

Here are the heavy-duty Velcro pieces that come with the Belktronix kit. There are also some small "L" brackets in the kit that I could also use to mount the potbox to the firewall, but I'll try the Velcro version first and see if it sticks (pun intended). The Belktronix system tries to make installing the potbox a no-brainer by allowing the user to put it right under the accelerator pedal. For the Civic, this works out quite well.

2008 100

Wiring Things Up and Testing

Open Source Civic EV Kit

Much of my time was spent wiring up the controller, charger and integrator box from the Belktronix kit. I had to unbolt the charger in order to get access to the fast-on connectors on the side of the main motor controller. The Belktronix instructions come with a checklist of things to do before powering up the system. I had my handy Fluke meter out to find any problems. Here's a top-down look at the vehicle integrator module all wired up.

2008 100

Rob Connelly's Front Battery Racks

Open Source Civic EV Kit

There's not much special about this project other than I'm trying to collect the information together into an open-source kit. "If I have seen farther than others it is because I have stood on the shoulders of giants" Many other people have done Honda Civic EV conversions before this one, which is why my job is so easy. I'd like to thank Rob Connelly for providing 3D drawings of his front battery racks so people can see different ways of doing things.

2008 100

Christmas Presents

Open Source Civic EV Kit

Santa was good to me this year. I received a Link-10 battery monitor from my parents. I don't think they understand what it does and why it costs so much, but okay, they got it for me anyway. The items on the right came from Belktronix. The wires on the upper left are the Link-10 voltage prescaler. The module on the upper right is the DC-DC to supply an isolated 12V to the link-10.

2008 100

Frustrations with Zolox sensor mount

Open Source Civic EV Kit

I tried installing the Zolox sensor mounting ring for the Warp9 motor from EVsource today. It looks like the holes on the mounting ring don't line up properly. The holes for the Warp9 casing don't match, so I had to drill them a bit larger so the bolts would go in. Here I've placed the spinning magnet onto the end of the tailshaft with a short 1/4 bolt to properly center it. If you look closely, the spacing is off so that the shaft isn't properly centered in the mounting ring.

2008 100

Add the Splash Guard

Open Source Civic EV Kit

I'd like to get the car off the jack-stands and back into a position where I can drive it while still adding things like the guages. After installing the speed sensor, the last thing needed under the car is the splash guard to protect water and grit from getting into the Warp9. After playing around a bit, I found that a piece of ABS plastic 15" x 18" and 3/16" thick will probably work.

2008 100

Taking a Break

Open Source Civic EV Kit

A few things that are in the works: getting the Civic S20 transmission to a precision measurement person to get an accurate diagram of all the holes and outline for repetitive fabrication of adapter plates ordering a clutch plate and sending it off to EV-America for a motor shaft adapter purchasing relevant EV kit parts (9" motor, etc.)

2008 100

Tachometer is Here!

Open Source Civic EV Kit

This is a cool day(And not just because it's freezing outside). The package with the custom tachometer from SpeedHut arrived. Although I received the 2-hole pillar pod last Friday, I wanted to show it here since I ordered both items from Speedhut. The wiring harness is nice and long. The small module in the lower left of the photo is the dash light interface which allows a variable dash light brightness to control the tach brightness as well. This is just too awesome for words.

2008 100

Charging parts back and more miles

Open Source Civic EV Kit

I received the fixed charger parts back from Belktronix on Friday and installed them with no problems. After going through a full charge cycle, I did find another Batmon board that was activating the shunt resistor at 13.5 volts instead of the expected 14.6 volts. I'll look into that early this week or send it back for repairs. After fixing up the charging system, I took a quick test drive with my friend Jonathan for about 7 miles and the car behaved well.

2008 100

Plastic Boxes and Speed Sensor

Open Source Civic EV Kit

I got some fun stuff today. The plastic boxes for the BatMons and the Zolox speed sensor with Warp9 mounting hardware came in. Here's a pile of 2x2" plastic boxes 1/2" high that fit the BatMon boards quite well. If I cut off one side, I should have at least some protection from splash and other grit that enters the engine compartment. Here's the Zolox speed sensor from EVSource. I don't know if it will work correctly with the SpeedHut tachometer that's coming, but I hope so.

2008 100

Ordering Gauges

Open Source Civic EV Kit

While I wait for the charging components to get fixed, I did some research on gauges to monitor the state of the system. My goal is to use as much of the existing dashboard as possible and then add low-cost gauges in order to prevent any motor problems and detect faults.

2008 100

Cleaning up Loose Ends

Open Source Civic EV Kit

After working with Bryan from Belktronix yesterday, I found out that I had blown some components in the IsoBatMon, the Charge Detector and one of the BatMon boards. Those went off in the mail this morning back for repairs. I'll try the system again when the parts come back. In the meantime, it looks like the speedomter is working again. I also purchased a new headlamp to fix a burned out right hi-beam. It turns out the problem wasn't the bulb but a *missing* fuse in the fusebox.

2008 100

Wiring up and Testing Batmon Boards

Open Source Civic EV Kit

Okay, it's time to get your wiring spaghetti on. I spent part of last evening (after fixing the speedo) and all of this morning wiring up the Batmon boards. In the process I blew the OVP channel on the IsoBatMon unit. Here I'm crimping yellow 3/8" ring terminals on all the blade fuse holders that will hold the 7.5A fuses. I tried to do as much as I could on a workbench instead of in the cramped quarters of the car. Okay, I've finished wiring up the front set of batteries.

2008 100

Fixing the Speedometer, Removing ECU

Open Source Civic EV Kit

During the test drive, I noticed that the speedometer wasn't working. It had worked fine before I removed the engine. After researching the Helms manual, I needed to get at the speed-sensor on the transmission to figure out what was going wrong. Fortunately I hadn't yet wired up all the BatMon boards, so removing the firewall batteries to get at the sensor only took a few minutes. Here's the firewall battery rack with two batteries removed to get at the speed sensor on the transmission.

2008 100

Fixing up the Rear Suspension

Open Source Civic EV Kit

Whew! I finally got my internet connection back up at home. This is the first of ten entries that will attempt to show many of the tasks I performed over the four-day Thanksgiving weekend. First up, we need to beef up the rear suspension to handle the extra 420 pounds of batteries in the trunk. As you may remember, I swapped out the front springs with beefier ones.

2008 100

Installing the Charging Outlet

Open Source Civic EV Kit

At some point, I guess we have to charge this thing. Most people like to be clever and put the charging outlet under the gas tank cover. I don't like this because it's near the back of the car, away from most charging station outlets at parking spaces. It also requires more routing of wire to get to the charger. Instead, I chose to simply cut a hole in the side of the front bumper and use a charging outlet from a boating store.

2008 100

Crimping the Battery Cables

Open Source Civic EV Kit

One of the major tasks during construction of an EV is properly crimping all the heavy duty battery cables together. Here's the process that I used. I measured the distance between the terminals that I needed to connect, subtracted 1/2" and then cut a piece of 2/0 gauge welding cable for that distance. Welding cable is much more flexible than typical 2/0 gauge wire, allowing it to snake around various car parts. The picture here shows a piece of cable and a special cable stripping tool.

2008 100

Installing the Batmon Resistors

Open Source Civic EV Kit

In order to shunt current around each fully charged battery, the BatMon boards use an external 3 ohm resistor. Since mounting these resistors involves drilling holes in metal, I wanted to mount them before mounting the BatMon boards to prevent metal shavings from sprinkling into the electronics. Here are two pictures in the rear trunk showing the drilled holes for the resistor mounting bolts. The BatMon resistors have mounting holes 2" apart that take 10-24 bolts.

2008 100

Routing the Cables Underneath

Open Source Civic EV Kit

Not surprisingly, we need to connect the batteries in back with the batteries in front and also include the main circuit breaker under the parking brake. These lines are typically routed under the car in the trough left by the exhaust system. Many people use pool tubing to protect the battery cables from road dirt. After looking at the tubing selection at the local hardware store, I opted to use reinforced radiator hose tubes (outside diameter 1", inside diameter 3/4").

2008 100

Routing the LVP/OVP Cables

Open Source Civic EV Kit

In addition to the thick, high-current battery cables, we need to route the OVP (over-voltage protection) and LVP (low-voltage protection) wires from the rear BatMon boards to the front BatMon boards. The instructions say to route these away from the high-current cables and away from each other to prevent noise. I decided to route these through the rubber plug that the fuel tank wires go through. Here is the rear seat lifted up and the fuel tank cover removed.

2008 100

Buttoning up the Exterior

Open Source Civic EV Kit

Even though all the BatMon boards are not wired up, I was itching for a quick test drive. It was time for me to get the wheels on the car and take it for a short spin. This is the picture of my front hallway closet. I had originally stored the tires from the Civic in the front hall, but my cats licked the brake dust off the inside, so I had to put them in the closet. They didn't fit that well and kept tumbling out every time I opened the door. As you can see, they just don't fit that well.

2008 100

Movies of the First Test Run

Open Source Civic EV Kit

Well, my home internet connection is still down, so I uploaded a few videos here for your viewing pleasure and to prove that I'm not just blowing smoke :) Thanks to my friend Rick for capturing these on my small camera. These are unedited and Rick tended to rotate the camera a bit. I'll probably make something more refined later. Here is a quick tour of the major components under the hood. Here is the Civic backing out of my driveway and taking off. It's nice and peppy!

2008 100

It's Alive! Updates coming.

Open Source Civic EV Kit

Okay, the cat is out of the bag. I've been working many hours a day over this four-day weekend to try and get the Civic running. As luck would have it, my internet connection went down Thursday morning and is still not back up (I'm typing this from work). I'll post all the progress and pictures when my connection comes back. Suffice it to say, I'm exhausted, but the wheels are spinning as of 12:15pm yesterday(Saturday).

2008 100

Arranging the Electronics

Open Source Civic EV Kit

The next step was to figure out where to put all the control electronics under the front hood to minimize wiring. The Belktronix system comes with velcro attached to the underside of most of its components. I was able to fit the Integrator and Charge Controller in the passenger-side nook, next to the main charging unit. I attached the IsoBatMon circuit to the top of the closest AGM battery (right side of photo) to minimize cable runs.

2008 100

Bolting Together the Front Battery Rack

Open Source Civic EV Kit

I'm taking a different strategy from many EV installations in the hopes that people can more easily put together a kit for the Civic at home. The intent is to make this kit easy to create and install Most folks weld together battery racks and then bolt them into the car (or sometimes weld them in). This strategy uses beefy angle iron pieces and 3/8" grade-8 bolts with nylock nuts to hold things together. I'll revisit whether this strategy is a good one or not after trying it out.

2008 100

Buying Heavy Battery Cable

Open Source Civic EV Kit

I spent last night visualizing how I could most effectively connect all the traction batteries with the least amount of welding cable and the shortest distance to the controller and motor. This morning I took some thick rope to serve as a fake battery cable and used it to measure the long cable lengths needed to connect the front and rear batteries. Measuring this is important because welding cable is expensive and you need to get enough but not too much.

2008 100

Hacking the Final Hold-downs

Open Source Civic EV Kit

I installed the remaining hold-downs for the 12V auxiliary battery and the extra battery in the rear trunk this evening. I hadn't designed these hold-downs before I sent all the pieces off to powder-coat, so I'll have to paint them with POR-15 protectant before I finish. Here's a picture of the 12V aux battery hold-down. The battery is a smaller motorcycle battery.

2008 100

Charger, Controller and Contactor Mounting

Open Source Civic EV Kit

Today involved trying to mount the major electrical components to the car. Before covering up the transmission, I thought it would be a good idea to fill it with transmission fluid. The Honda Civic specifies 10w-30 oil for the transmission. Since the fill hole is really hard to access, I used a funnel attached to a plastic hose to get the oil in. Before mounting the plastic panel to mount the EV components on, I drilled two 3/16" holes, 6 3/4" apart on the passenger side battery support.

2008 100

Re-Using Computer Wires

Open Source Civic EV Kit

The Belktronix system instructions call for attaching all the Batmon boards with twisted pairs of wires. I couldn't find a spool of twisted wires at the hardware store, but it dawned on me that most desktop computers use twisted wires to connect the motherboard with the switches/LEDs on the front panel. So, I went over to my friend non-profit computer recycler FreeGeek and picked up a handful of twisted wires out of their wire recycling bin for $1.

2008 100

Scoping out the Trunk

Open Source Civic EV Kit

In the spirit of keeping the kit simple, I'm seriously considering not having the builder have to cut into the floor of the trunk. I registered the Civic today at DMV and washed it to get all the grime off. The car is quite zippy as a gas car and is fun to drive. I also removed all the upholstery from the trunk and took some measurements to see just how I could mount six batteries back there. Here's a center view of the trunk.

2008 100

Charger/DC-DC Arrives

Open Source Civic EV Kit

The last piece of equipment from Belktronix arrived today. Here's the charging system from Belktronix. The 1200 watt charger is combined with the DC-DC converter on the right. The small black box on the left is the charge controller box which interfaces with all the Batmon units that monitor the voltage on each battery. I'm psyched that I finally have all the critical pieces and nothing left is holding me back. Last week, I also dropped by my favorite overpriced EV parts store: West Marine.

2008 100

Starter Blockoff Plate Template

Open Source Civic EV Kit

I took some time this morning to finish all the vacuum pump connections and installing the wiring harness discussed a few posts back. Before installing the batteries in the firewall rack, I needed to measure the starter block-off hole to make a cover for where the starter motor used to be. Here's the engine compartment with the engine wiring harness plugged in and tie-wrapped to several locations.

2008 100

Component Placement on Plastic Control Board

Open Source Civic EV Kit

With all the components under the firewall rack installed, I put the four remaining batteries in the rack and started figuring out the placement of parts on the control board. Here is the tentative placement of charger and controller. The contactor is off to the far right. I purchased a piece of black "UHMW" plastic (28" long x 8 1/2" wide by 1/2" thick) to mount the components on. My EV cohort Ron used this plastic in his VW Jetta EV at Shorepower Technologies and it seems to work well.

2008 100

Installing the Vacuum Pump

Open Source Civic EV Kit

I installed the Gast vacuum pump and pressure tank next. First, I installed rubber motor mounts underneath the Gast vacuum pump. Since I'm mounting this on uneven pieces of metal, I needed to add two 1/16" thick 1"dia. fender washers to the two feet on the front. The rubber feet serve two purposes: keep the motor vibration from rattling the chassis and raising the pump to clear the supporting angle iron. The rubber feet are 1" in diameter, 3/4" tall (rubber portion) with 1/4" threaded ends.

2008 100