Project: Zombie Insight (2000 Honda)

[MechanicalRandall]

Originally Posted by RobertSmalls

I've assembled a MIMA controller

I just finished installing the DIY MIMA as well...Still trying to figure out all the functions. Where/how did you mount your joystick, and also how did you mount the display?

Originally Posted by RobertSmalls

I also noticed moisture under the carpet, and I'm not sure that can be helped either.

Ouch, I would figure out where it was coming in if I were you. That can only get worse...

[RobertSmalls]

Oh, you're the guy I have to thank for the updated partslist .xls! I'm curious, did you end up with ten CPU sockets as well?

I just took the bare PCB of LEDs and stuffed it between the steering column cowl and dashboard. It needed a thin shim to fit snugly.



I swapped my IMA battery with my spare to see if my limited assist problem goes away. It'll be in the car on the grid charger for 36 hours to bring it out of storage, so I'll know on Wednesday if the battery was my problem.

While I had the battery out, I wanted to see how well some 40Ah LFP cells would fit in place of the stock 6.5Ah NiMH. I think LFP are more appropriate for a PHEV, and if you believe Thundersky, their cells will last until well after you're bored with them.

Anyway, each of these boxes represents two 40Ah cells, so I'd need 25 boxes, 50 cells, to reach the required voltage to replace the IMA battery. The boxes are a little taller than the cells, which will allow room for wiring and a BMS slave.





32 out of the 50 cells fit in place of the IMA battery module with no problem. An additional 8-10 cells would fit where the inverter cooling fan duct is. I'd have no qualms about using cabin air to cool the inverter. Maybe in the winter, I could recirculate that air through the cabin for heat.

There's room for a dozen or so cells to the left of the driver's side frame rail, perhaps 6 cells under the fuel filler pipe, and a few cells in front of the IMA box.



I've been thinking about an Insight-bodied EV conversion. But to do it right would be at least $10,000. The results would be nice, though. I'd put the batteries where the gas tank is right now (in addition to in the engine bay and exhaust tunnel?), and get rid of that damned IMA box. I'd finally have the cargo space of a CRX.

[MechanicalRandall]

Originally Posted by RobertSmalls

Oh, you're the guy I have to thank for the updated partslist .xls! I'm curious, did you end up with ten CPU sockets as well?

Yes I have quite a few parts I had to buy 5 or 10 of, especially the sockets.

What about the joystick? I'm trying to figure out what to do with it. I have access to a lot of great equipment so I was thinking of relocating the Mode1 and Mode2 buttons to the dash and making a tiny PCB just to mount the joystick. I also plan to design some sort of housing which would replace the shifter knob or mount just below it. I think the existing design with the buttons near the joystick is needlessly bulky and I don't think the buttons need to be nearly that accessible.

[RobertSmalls]

I've got my joystick and a wad of toolbox liner zip-tied to the handbrake. It's fine, but not great when you're rowing through the gears.

Peter Perkins has his on the steering column, between the wheel and the wiper stalk I believe. It has a 6" handle, and you can operate it with both hands on the wheel. That seems very appropriate for PHEV'ing, and I plan to put one of my joysticks there after I decide on a fastening method. Four sheet metal screws, maybe?

[MN Driver]

Originally Posted by RobertSmalls

While I had the battery out, I wanted to see how well some 40Ah LFP cells would fit in place of the stock 6.5Ah NiMH. I think LFP are more appropriate for a PHEV, and (removed link since it doesn't let me quote it due to having under 5 posts, shakes fist), their cells will last until well after you're bored with them.

Anyway, each of these boxes represents two 40Ah cells, so I'd need 25 boxes, 50 cells, to reach the required voltage to replace the IMA battery. The boxes are a little taller than the cells, which will allow room for wiring and a BMS slave.

32 out of the 50 cells fit in place of the IMA battery module with no problem. An additional 8-10 cells would fit where the inverter cooling fan duct is. I'd have no qualms about using cabin air to cool the inverter. Maybe in the winter, I could recirculate that air through the cabin for heat.

There's room for a dozen or so cells to the left of the driver's side frame rail, perhaps 6 cells under the fuel filler pipe, and a few cells in front of the IMA box.

I've been thinking about an Insight-bodied EV conversion. But to do it right would be at least $10,000. The results would be nice, though. I'd put the batteries where the gas tank is right now (in addition to in the engine bay and exhaust tunnel?), and get rid of that damned IMA box. I'd finally have the cargo space of a CRX.

How many more cells can fit to the left and right of the spare tire area where they packed in the styrofoam inserts for the cd changer option and the gap of nothing on the opposite side? It would be a pain to wire them there but might be worth it if you are trying to keep the spare tire where it is and not loose as much useful cargo room.

I see you have run into my little thought tunnel about going either EV, extended NiMh or Lithium PHEV. It's proving to be a very difficult decision for me to make. If I go with upgrading my capacity using NiMh by using an extra Insight parallel set or two using a pack of our familiar 5 cell 5.5Ah sticks(hopefully they would fit in a decent fashion), I could be up to a little over 15Ah if I'm really lucky(if I get the capacities matched up well enough and the cells are in decent shape) but with a fair amount of added weight and lost space, I would be inclined to remove the cells if I went on an extended trip to lose the weight and gain the space back.

My suggestion is if you go with 40Ah LiFePO4 cells, to go with the CALB cells (formally Sky Energy cells), they will provide you with less voltage sag than the Thunder Sky cells or Hi Power cells. People on DIYelectricCar using these have said that their capacity is higher than what their ratings are and those using Thunder Sky don't see as much of an advantage. With less voltage sag, this demonstrates less internal resistance which means they should also work better at lower temperatures and withstand the 100 amp discharge and 50 amp charges with less internal stress. I think they would likely provide you with more life with this application even though their spec sheet doesn't say so. It seems to be a bit of a wash though because there are more distributors for Thunder Sky out there now and the best one for Sky Energy had a serious issue recently where nobody got their Thunder Sky cells that they paid for while they 'liquidated' them to others in 'bankruptcy'. If I see a killer deal for Thunder Sky or Sky Energy cells, I'll probably take the killer deal and run with it and install a bigger pack. Until then, I might just have a parallel pack or two of NiMh and call it good knowing that I can keep my spare tire where it is.

The more that I think about it, the less I think that I'm going to go with turning my car into an EV. I did a cost analysis recently and it might be best to wait until I can get a used Leaf, Volt, or a different EV for peanuts at the 10 year mark. I'd enjoy the project of converting but if I go PHEV and even going with MIMA, that is extra money that I will feel was wasted if I end up going EV later. If I were to go with EV, I'd have to do it ASAP for it to be cost effective versus continuing to burn gas and buy things that only work with the gas components, IMA, and stock systems in the car.

"Peter Perkins has his on the steering column, between the wheel and the wiper stalk I believe. It has a 6" handle, and you can operate it with both hands on the wheel. "

I'm not entirely sure that is the case, that may have been his second Insight that he said he wife was driving(the one that he was installing the 8Ah LifeBatt cells into, and now it is the 20Ah cell_man cells, brand removed due to possible issue with that 123 company that starts with an A, not being too happy about us having those cells). He has installed a simple two-way switch where one way controls the clutch switch, the other the brake switch to prevent assist or to allow for regen without using the brake pedal.

[RobertSmalls]

MN, I'd encourage you to try out PHEV'ing on the stock pack before you decide whether to install additional capacity. Today's trial confirms the conventional wisdom that plugging in a mild hybrid makes a very poor EV.

Longer trips give you a much wider selection of when you want to use your assist. If I had used it just for accelerating today, I'd have come home with a mostly full battery. If I had waited for the thermostat to open, I would have hardly used assist at all.

Brief description of Peter's joystick placement: New MIMA Thread (all MIMA discussion goes here) - Page 53 - Insight Central: Honda Insight Forum

How many cells fit aft of the IMA box? About six on each side. But that's a crumple zone, and it gets used often enough from what I've seen. Another reason to avoid putting cells that far back is it will mess with your center of mass, crosswind stability, and yaw intertia.

Where do you go to price out cells? Nissan allegedly pay $375/KWh! The stuff I've seen is $600/KWh for crap Chinese cells, even when you buy 50 cells at a time.



I did something with MIMA the other day that I REALLY enjoyed. It usually takes me up to three miles to get warmed up and into LB on 40mph roads. I entered LB in under a mile the other day, by giving it enough gas to cruise at 50mpg and using regen to hold my speed down. There's no better time for regen than when the engine's cold.

[RobertSmalls]

I checked out those CALB cells. Prices and specs are similar to Thundersky, but there are a few differences in the datasheets. Thundersky's sheet is more complete, telling you how much capacity to expect at higher C-rates and lower temperatures. TS also say it's okay to charge or discharge at -45°C, versus the 0°C charge / -25°C discharge of the CALB. I can handle -25°C, but I can't accomodate a battery that can't plug in or regen below 0°C.

By far the biggest problem with both datasheets is the "standard current = 0.3C", i.e. all the other data is at 0.3C = 12A, including the cycle life data. It would take over two hours to reach 70% DoD at that C rate, and I don't know many people who drive (PH)EVs two hours a day, excluding stops and coasting.

As an experiment, I started with three bars indicated SoC and a topped off battery today. Instead of allowing the car to charge the already topped off battery for a minute before it recalibrates the SoC gauge, I tried starting off with assist.

As I expected, you can draw down the battery and the SoC gauge stays at three bars until you hit the low voltage cutoff. What I did not count on was, I also got three bars of background charging which I could only get rid of by constantly requesting assist. Background charing killed any hopes of lean burn. I'm going to go back to powering up the BCM while charging and see if the MPG improves. I got 69mpg + ~1KWh = 53mpge today on 15mi of city driving.

[Artric]

Two questions for you:

Can you explain how to calculate MPGe?

Do you have any idea roughly of how much extra power it takes to power the BCM? Have you tested with a Kill-A-Watt?

Keep up the great work!

[RobertSmalls]

Originally Posted by Artric

Can you explain how to calculate MPGe?

Oh boy. I could spend hours explaining that one.

It depends on what you're trying to achieve by using electricity instead of gas. If you're in it for the engineering challenge or CO2, I recommend 16KWh = 1 gal. So every night I plug in is equivalent to about 0.06gal. By a cost-equivalent method, it would be 24KWh=1gal for me.

(Miles driven) / (mpg) = gallons burned. Then add in the adjustment (e.g. 0.06gal), and divide miles driven by adjusted gallons to get mpge.

You've been using MIMA longer than I have... how many gallons does it save you each time you charge the battery, and do you have KaW data from your charger?

Originally Posted by Artric

Do you have any idea roughly of how much extra power it takes to power the BCM? Have you tested with a Kill-A-Watt?

I do not yet have that data. Based on my experience so far, I'd say starting with a full SoC gauge is worth dozens of Wh, so I'm sure powering the BCM at night will pay off.

If you go with the faster charger you mentioned, the BCM and fan wouldn't have to run for twelve hours like mine do, so charging efficiency would increase as a result.

[Richy797]

Hello, This is my first post. I have purchsed a 2004 Honda Civic Hybrid which is salvage and hasn´t run since march this year. I´m fixing it but i´m afraid of the IMA battery condition since it´s unknown to me. The car has 246k miles on the odometer reading. Any advices?, in case I want to build a Grid charger like the one RobertSmalls shows, does any one knows on how to connect it to the battery?.
Thanks!!