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mpg_numbers_guy · 06-19-2019, 12:28 AM

Warning: Image heavy.

-

Deleted the IMA battery today!

Finally had a full day to work on the Insight, so I spent it getting the IMA deleted from the car.

My IMA is healthy and throws no codes. The one time it threw a code was merely a ground strap issue that was swiftly fixed.

However, as a hypermiler, the IMA is just dead weight. As we know, energy is not wasted when we accelerate, but rather when we brake and turn that energy into brake dust. Hybrids attempt to counteract this inefficient driving by capturing that energy through regenerative braking, and then using that energy to provide faster or more fuel efficient acceleration.

The hybrid system is less efficient than a traditional gasoline motor, because the regenerative braking and charging process is very inefficient. Hybrids only return better fuel economy for inefficient drivers (unless you spend money on systems like MIMA to give you manual control over the battery).

With all that being said, a hypermiler can get the same fuel economy in an Insight without the hybrid battery. As proof, consider the fuel logs of any one of us who have disabled and/or deleted the IMA battery.

When a hypermiler can get the same fuel economy in a hybrid as in a non-hybrid (given that they are the same vehicle), then the hybrid battery merely becomes dead weight that slows acceleration and reduces fuel economy.

Thankfully, in Honda hybrids, the hybrid battery can be deleted without affecting the vehicle's functionality. According to Insight Central, the hybrid battery weights 69 lbs, and the computers and wiring add another 3lbs. 72lbs is a decent weight on a car that weighs less than 1900lbs stock. On top of the 32lbs of the passenger seat I also removed today.

Plus, the IMA battery takes up a lot of storage room. While the Insight's hatchback design helps, not having rear seats to fold down for storage does hamper it a bit. With the IMA deleted, storage space becomes abundant.

Anyway, long story short, that is why I'm deleting the hybrid battery: weight reduction and storage space. Not because my IMA battery is bad.

Now on to something that's hopefully a little more interesting than me just rambling.

I followed mudder's thread over on Insight Central titled "How to Completely Remove Your IMA Battery".

Arduino bypass was provided by Ecky, passed down after his K-swap.

Once the IMA battery is removed (there are tutorials out for this, or you can just follow the bolts and go by what you see, it isn't that complicated), the output high voltage leads from the IMA need to be connected directly to the DC-DC. Prior to this, they were connected to the IMA battery, and then leads from the IMA went to the DC-DC.

I opted to not cut into anything, so I used some modified spade connectors to connect to the existing plug:

Normal spade connectors are not wide enough to plug in, so I expanded them by tapping them down onto a flathead screwdriver. I later used pliers to flatten them to ensure a tight connection.

Here is a picture of a modified connector on the left, and an unmodified one on the right.

There is a fuse on the IMA battery that needs to be disconnected and reused here. If I have my facts straight it's a 250 VDC fuse rated for 30 or 40 amps. This fuse needs to be in place between your connections of the positive leads.

Here is a picture of the fuse connected to the positive output lead:

I used 10-gauge wire to connect the leads. All materials used are rated for 600 volts. Here is a picture of the completed setup:

More pictures showing the setup from different angles:

The arduino connected for testing purposes. It's a bit more secured now and will be even more so once I get the rear rebuilt.

After testing and verifying that the car started fine with no warning lights, I sealed up the connections with electrical tape and tried to add some semblance of organization there for now.

So now here is my current view from the back of the car. Next step is to relocate the DC-DC converter to the spare tire area and then start building up the sides and recarpeting the rear to reclaim all that newfound storage space.

More details on this mod can be found on mudder's thread over on Insight Central here. I skipped some of the details and focused more on the specifics of what I did since there is plenty of detail on it on the IC thread.

No CEL, No IMA light, No IMA battery! Why even did Honda weigh down this car with a hybrid battery anyway?

~ Happy ecomodding!

06-19-2019, 12:28 AM	#199 (permalink)
mpg_numbers_guy Master EcoModder Join Date: Feb 2018 Location: VA Posts: 1,372 Toby - '13 Toyota Prius C Team Toyota 90 day: 63.99 mpg (US) Daz - '15 Mazda 3 iTouring w/ Tech Package Team Mazda 90 day: 38.2 mpg (US) Thanks: 324 Thanked 483 Times in 368 Posts	Warning: Image heavy. - Deleted the IMA battery today! Finally had a full day to work on the Insight, so I spent it getting the IMA deleted from the car. My IMA is healthy and throws no codes. The one time it threw a code was merely a ground strap issue that was swiftly fixed. However, as a hypermiler, the IMA is just dead weight. As we know, energy is not wasted when we accelerate, but rather when we brake and turn that energy into brake dust. Hybrids attempt to counteract this inefficient driving by capturing that energy through regenerative braking, and then using that energy to provide faster or more fuel efficient acceleration. The hybrid system is less efficient than a traditional gasoline motor, because the regenerative braking and charging process is very inefficient. Hybrids only return better fuel economy for inefficient drivers (unless you spend money on systems like MIMA to give you manual control over the battery). With all that being said, a hypermiler can get the same fuel economy in an Insight without the hybrid battery. As proof, consider the fuel logs of any one of us who have disabled and/or deleted the IMA battery. When a hypermiler can get the same fuel economy in a hybrid as in a non-hybrid (given that they are the same vehicle), then the hybrid battery merely becomes dead weight that slows acceleration and reduces fuel economy. Thankfully, in Honda hybrids, the hybrid battery can be deleted without affecting the vehicle's functionality. According to Insight Central, the hybrid battery weights 69 lbs, and the computers and wiring add another 3lbs. 72lbs is a decent weight on a car that weighs less than 1900lbs stock. On top of the 32lbs of the passenger seat I also removed today. Plus, the IMA battery takes up a lot of storage room. While the Insight's hatchback design helps, not having rear seats to fold down for storage does hamper it a bit. With the IMA deleted, storage space becomes abundant. Anyway, long story short, that is why I'm deleting the hybrid battery: weight reduction and storage space. Not because my IMA battery is bad. Now on to something that's hopefully a little more interesting than me just rambling. I followed mudder's thread over on Insight Central titled "How to Completely Remove Your IMA Battery". Arduino bypass was provided by Ecky, passed down after his K-swap. Once the IMA battery is removed (there are tutorials out for this, or you can just follow the bolts and go by what you see, it isn't that complicated), the output high voltage leads from the IMA need to be connected directly to the DC-DC. Prior to this, they were connected to the IMA battery, and then leads from the IMA went to the DC-DC. I opted to not cut into anything, so I used some modified spade connectors to connect to the existing plug: Normal spade connectors are not wide enough to plug in, so I expanded them by tapping them down onto a flathead screwdriver. I later used pliers to flatten them to ensure a tight connection. Here is a picture of a modified connector on the left, and an unmodified one on the right. There is a fuse on the IMA battery that needs to be disconnected and reused here. If I have my facts straight it's a 250 VDC fuse rated for 30 or 40 amps. This fuse needs to be in place between your connections of the positive leads. Here is a picture of the fuse connected to the positive output lead: I used 10-gauge wire to connect the leads. All materials used are rated for 600 volts. Here is a picture of the completed setup: More pictures showing the setup from different angles: The arduino connected for testing purposes. It's a bit more secured now and will be even more so once I get the rear rebuilt. After testing and verifying that the car started fine with no warning lights, I sealed up the connections with electrical tape and tried to add some semblance of organization there for now. So now here is my current view from the back of the car. Next step is to relocate the DC-DC converter to the spare tire area and then start building up the sides and recarpeting the rear to reclaim all that newfound storage space. More details on this mod can be found on mudder's thread over on Insight Central here. I skipped some of the details and focused more on the specifics of what I did since there is plenty of detail on it on the IC thread. No CEL, No IMA light, No IMA battery! Why even did Honda weigh down this car with a hybrid battery anyway? ~ Happy ecomodding! Attached Thumbnails __________________ 2013 Toyota Prius C 2 (my car) 2015 Mazda 3 iTouring Hatchback w/ Tech Package (wife's car) Last edited by mpg_numbers_guy; 06-19-2019 at 12:38 AM..