2008 Prius Traction Battery Replacement (planning ahead just in case)

[Vman455]

Originally Posted by JSH

I can see it. Lots of short trips doesn't compute with my lifestyle but it does for lots of people. I knew people in Alabama that drove their kids 1/4 mile to school and drove between stores in a strip mall.

This drives me nuts. There's an apartment complex less than 1/4 mile from my school (literally just across a municipal park) that caters to students; at least once a week as I drive past, I see someone pull out of the apartment parking lot, drive the short distance and turn into the school entrance.

[Xist]

How bad is the parking at your school? When I was at ASU there were always girls walking into class late and complaining about parking, waiting in line to pay for it, etc.

My program was 95% male, so if it happened with the guys, it was much less common.

Batteries inside a car running the air conditioning are one thing, but if you drive 15,000 miles a year, and average 50 MPH, you are spending three hundred hours a year driving, although I would expect double that.

What about the other eight hours of summer heat each day?

[broski499]

I bought the Dr. Hybrid app on ios and found it didnt work with the OBDI device I had. Apparently, there is a wide range of obdi sensors and some are garbage when it comes to what kind of data they pull from the OBDI port.

Luckily the Dr. Hybrid app has a blog and they went through and tested a bunch of the devices to see which ones work for their device both in android and iOS.

For iO2 the Carista OBDI bluetooth sensor is your best option as you get the bettery data. They have different tests you can run to get an idea of your battery health. They are only $20.

It has you charge up your battery and then by utilizing your AC, headlights, and radio to discharge the battery it calculates how long it takes to drain your hybrid battery. Really an interesting process.

I tried to save the photo of the results but the app crashed, I'll screenshot it next time. You also get real-time data on the voltage across your battery packs. I'll take a screen shot and post it here next time I do the test.

My battery pack was shown to be at 54% health. For a 2008 Prius I thought that was pretty good.

My question now is would the battery conditioning products help prolong my battery health, and if so by how much? I know that they help rebalance the batteries and bring back some of the battery life, but how much is to be expected?

[redpoint5]

Originally Posted by broski499

My battery pack was shown to be at 54% health. For a 2008 Prius I thought that was pretty good.

My question now is would the battery conditioning products help prolong my battery health, and if so by how much? I know that they help rebalance the batteries and bring back some of the battery life, but how much is to be expected?

I don't know what 54% health means. Is that a measure of capacity compared with the rated new capacity? That doesn't seem very good to me because that doesn't mean you have half the life left. I'm guessing the car will fail to drive way before reaching 0%.

No idea how effective external chargers are for preserving hybrid batteries.

[broski499]

Originally Posted by redpoint5

I don't know what 54% health means. Is that a measure of capacity compared with the rated new capacity? That doesn't seem very good to me because that doesn't mean you have half the life left. I'm guessing the car will fail to drive way before reaching 0%.

No idea how effective external chargers are for preserving hybrid batteries.

In this same threat, someone stated that the 2007 Prius Battery packs are predicted to start failing around now. Yeah I meant capacity. I'll double check what the app said. I'm curious as to how much this limited capacity affects the MPG I'm able to get.

What was really interesting is you are able to see the actual percentage of charge on the app versus looking at the Prius Info screen. When the app said that my battery was at 55 percent the prius info area was showing a purple battery. Doesn't look like I'm really able to access a large portion of the battery to actually use for hybrid assist.

Has anyone done a battery replacement and then seen a noticable MPG gain?

[S Keith]

Originally Posted by broski499

I bought the Dr. Hybrid app on ios and found it didnt work with the OBDI device I had. Apparently, there is a wide range of obdi sensors and some are garbage when it comes to what kind of data they pull from the OBDI port.

Luckily the Dr. Hybrid app has a blog and they went through and tested a bunch of the devices to see which ones work for their device both in android and iOS.

For iO2 the Carista OBDI bluetooth sensor is your best option as you get the bettery data. They have different tests you can run to get an idea of your battery health. They are only $20.

It has you charge up your battery and then by utilizing your AC, headlights, and radio to discharge the battery it calculates how long it takes to drain your hybrid battery. Really an interesting process.

I tried to save the photo of the results but the app crashed, I'll screenshot it next time. You also get real-time data on the voltage across your battery packs. I'll take a screen shot and post it here next time I do the test.

My battery pack was shown to be at 54% health. For a 2008 Prius I thought that was pretty good.

My question now is would the battery conditioning products help prolong my battery health, and if so by how much? I know that they help rebalance the batteries and bring back some of the battery life, but how much is to be expected?

There's 3 questions in there...

Yes. Near new. Unknown.

Here's something I posted in 12/15 showing the before and after reconditioning tests using a similar discharge method (but more aggressive as I was modulating throttle):

https://priuschat.com/threads/quanti...charge.160062/

The images are broken from when Dropbox changed things, but the table summarizes it nicely.

Hybrid Automotive put it on their website with my permission:

https://hybridautomotive.com/indepen...tream-testing/

After I conducted that testing, I became an authorized installer for HA products. I know the owner, and I have some of their equipment. I do NOT receive any compensation for recommending them.

To your last question, the subject car operated trouble-free (battery-wise) for another 3 years with no additional reconditioning treatments. The car was otherwise fairly abused having been in multiple accidents and barely surviving their teenage daughter's first years of driving. The car eventually coded, but the owner was done with it, and some foolish dealership offered him $2400 for it with whatever was wrong with it.

In my experience, when a battery in the Phoenix area fails, it is typically at the 25-30% state of health (25-30% of rated capacity) when a cell drops out. In milder climates, this is not true as batteries fail at much higher states of health because less capacity is lost due to heat.

Note that any measurement reported by Dr. Prius or Hybrid Assistant or even my numbers reported with Techstream is essentially reporting the health of the WEAKEST BLOCK as the 14 block voltages are what determine utilization, not the total pack voltage. Most packs have a wide range of deterioration on a block basis.

[redpoint5]

So perhaps Broski has 30% more years or miles left before the battery is kaput? That's like 3 years.

Makes me curious about remaining capacity % on my PiP. Anyone know of a decent method to determine this? I have Torque Pro, and can measure wall kWh as well as the kWhs the Prius reports as having taken.

[S Keith]

Originally Posted by redpoint5

So perhaps Broski has 30% more years or miles left before the battery is kaput? That's like 3 years.

Deterioration accelerates. A linear extrapolation is too optimistic.

[Xist]

Originally Posted by S Keith

Deterioration accelerates. A linear extrapolation is too optimistic.

I think this is the longest we have gone without discussing my crazy exes! :P

[roflwaffle]

Originally Posted by S Keith

Deterioration accelerates. A linear extrapolation is too optimistic.

From what I've read it depends on what's causing the deterioration. On page 18 of this pdf, the authors differentiate between mechanical deterioration, which like you said accelerates capacity deterioration at some point, and chemical deterioration, where capacity deterioration tends to decelerate over time/cycles.

https://www.nrel.gov/docs/fy14osti/62813.pdf