Honda Insight Battery discharge test

[Uhtrinity]

I have been running my Insight as a PHEV for a year now and wanted to see how the twin battery packs are holding up. The parallel configuration has been in place for almost 14 months.

I charge about 5 nights a week on average, so that works out to about 52 weeks X 5 charges = 260 charges @ ~7 cents each or $18.20 for the whole year.

My winter mileage went up 15 mpg (from 50mpg to 65 mpg) and the summer average has been running 80 - 85mpg. These are tank averages, not just highway miles.

First off, the batteries had taken about 1.8kW/hrs of charge the night before and had been close to empty at start.

Results:

Start temps: 86F / 82F
End temps: 92F / 86F

Average Discharge: 50 Amps, no gas pedal pressure.
Average speed: 35 - 40mph
Distance traveled: 5.5 miles in ~9:20
Calculated Ah: approx 7.5Ah used, the batteries actually have 13Ah, but for longevity doesn't use it all.
Final mpg: 150mpg ++ Final l/100km: .1l/100km (2300mpg)

Last years discharge test netted about 9:45, discharge was approximately 50 amps.

In all it looks like there was little to no capacity loss. My primary pack is a 2004 Civic NiMH, the secondary pack is the stock pack from the car, a 2000 Insight NiMH pack. Both rated at 144 volts and 6.5 AH each.

Youtube link of the run - kind of boring, but cool to see the mpg gauge pegged at 150mpg

 

[SickBeast]

Interesting. How hard was it to add in the additional battery pack? How much did it cost?

 

[PottedMeat]

Cool info.
The video reminds me how much I hate the 'instrument cluster' and touchscreen on the Prius. Toyota had to go all weird and shit.

How much was the 2004 Civic NiMH pack?
How did you get the current data?
Can you get actual current usage and voltage through the OBD-ii connector?

 

[Uhtrinity]

The Civic pack cost $250 shipped just over a year ago from a junk yard and I was the first to verify they were an exact match for the Insight subpacks. The charger components ran another $75. Mima, the addon computer / joystick was the most expensive at $750, but was the component that allows you to use the extra juice. In fact I found mima to be limited with just the stock battery. This isn't including my time in learning how the car works.

Mima displays the current data based on four charge leds and 4 discharge leds. The discharge leds are worth 25 amps each when fully lit up, At the beginning of the video you can see the two temp gauges (one for each battery pack) and the mima display. I have also verified these values against a high current DC amp meter. The extra pack was tricky to safely implementing as I had to figure out how the cars cars safeties work. When I turn on the key two HV relays engage connecting the packs. If either pack hits 130F the system disarms, stock the car disarms at 145 - 150F, I wanted to be safe to protect the car and batteries. The cars Battery management actually manages both packs ensuring they don't get overcharged or drained to low.

No on pulling that data through an OBDII, I wish as I have all of the equipment.

There is a guy in England who is deciphering all the serial bus traffic (hex values) and has isolated the display data for charge / regen as well as the battery gauge. It will be exciting to see what can be done with that information.