Prius Battery Replacement (GenII) Like you've never seen - NEW Cylindrical Cells

Do a baseline mileage test. Driving around expecting better mileage is not a good calculation. You may be a lead foot. You may not know how to hyper mile you may have a bad commute for mileage your engine may be shot etc lots of variables.

Find a nice straight road nice and flat. Rest the mileage calculator on the mfd zero it out set your cruise control control for 60 miles an hour. No lights on no heat on no ac on no radio on all windows closed tires at 35-40 just drive like that for about 3-4 miles. Don't touch the gas don't touch the brakes.

What does the mfd report after 3 miles? Thats pretty much the best the car can do.

My car at 160,000 miles tires at 35 psi says 60 mpgs with new NPB system.

 

Talking percentages is completely nebulous on this battery alot of it depends on the battery age. When my car was new one purple bar was no big deal. It would charge right back up almost instantly.

13 years later on a prolong propped up battery one purple bar the car was a dog. No bars or a red bar it was non existent no battery contribution at all in fact the car was scary useless as the engine not only had to power the car it also had to charge the empty old very hungry battery. When I hit my first red bar I new it was done and bought the NPB system and sold my Prolong.

Now after months of ownership of a NPB I have never seen anything less then 3 blue bars and neither has my wife.

The older the battery the hungrier it is. It just wont hold a charge.

 

I'm confident that I haven't taken a hit in mileage with the NPB upgrade, it seems to be very similar to what I was experiencing before the HV bit the dust. I was hoping to get a reliable replacement for the failed HV battery that didn't require me taking the pack out every few months and doing another module swap and re-balancing. What I wasn't expecting is that I'd get to experience/remember what the acceleration was like when the car was new. Since the battery capacity has been diminishing over time, I guess that I hadn't really noticed the change. That was a very pleasant surprise and a unexpected bonus.

I am curious about all aspects of the new battery's performance, but between working from home right now and a reduced commute once I do start going back in the office, I don't think it will be a fair comparison to my old commute (45-60 minutes). When I have taken a drive of over half an hour, the first 5 minutes is usually around 25 mpg, which has always been the case when the engine is cold. The next 5 minutes is usually in the 40s, and after that I'm averaging around 50 mpg. On rolling secondary roads I can get it up around 70 or 80 for stretches, and average well into the 50s. I'm pleased with the performance. The interior is a little worn and the clearcoat is peeling, so it doesn't exactly look like it did when it was new, but it sure is driving like it used to!

 

I replaced the factory modules with NPB ones on our (now daughter's) 2005 in early August, about 3k miles ago. So far and there is nothing to suggest this will change, the car is "as new" with identical performance to Toyota modules prior to failure.

She does not record fuel purchases and the lie-o-meter is worthless, she like other millennials, makes every attempt to USE UP anything she posses, so idling and sitting in the car for hours doing nothing but looking at the phone is not going to make anything last longer. Just say'n.

 

Kind of a boring report, but have about 2000 miles on the NPB kit and everything is still working great. I am driving the car almost daily, but not commuting to work has really reduced my mileage totals.

 

yep I have the same experience with my NPB kit. Works great so far. Very well designed kit easy to install.

 

Happy to report back in exact 2 years that she's still running great.
About 11000 miles on it since then due to less driving in COVID.
MPG was terrible in winter, but now it's back to 50ish range.

 

Whenever I get into terrible mileage season I remind myself that my 2008 Corolla gets worse and most others on the road are getting much worse.

 

What is the part number for the orange receptacle that is soldered to the computer ecu? This thing always has corrosion and carbon tracing we need to get that taken care of so it doesn't spread onto your new wiring harness.

 

Don't think that's a serviceable part. Would be difficult to get it out and replace anyway. There's plenty of G2 ecu's for sale on eBay.

And if the socket is corroded usually so is the connector.


04-09 TOYOTA PRIUS Hybrid Battery Control Module Computer ECU ECM 89890-47092 | eBay

 

I too replaced the oem pack with the NPB pack just over 2 years ago with no problems at all, 06' prius w/165k still running good. I get anywhere from 50-60mpg depending on #1 how it is driven #2 what the outside temp is, and #3 try not to park it overnight higher than 60SOC, overcharge it especially by too much regen braking (if it is over 60SOC drive it until its around 58-60DOC before parking). We have some hills here and can get it upto 68 or even over 70SOC! Of course I try to keep it lower toward the 60SOC range. Recently I noticed on the scan gauge the SOC was going upto 80SOC and with normal driving the SOC could very quickly go down to even 20SOC, then it would slowly charge back up to 60 range until the next event (could be 80+ or 20) so I decided to clean the bussbars and Vsense eyelets on the harness thinking they might be dirty. This fixed it sort of for a while, then the other day I was driving less than 35mph when bam it went all the way upto100SOC and got the red triangle of death! It seemed to go back down somewhat quickly with normal driving. The car still drives ok so I got it home and proceeded to park in the garage. Today I will go out again with the Scanner so when it fails again I will do a screenshot of the bat ECU params. But I believe there maybe a shorted cell or something but there is no overheating at all. Aux battery maybe a little weak but when running it's at 13.8V and when shut down for a few mins. it goes down to 12.2, so I could imagine what it is in the morning. So I remove the negative of the aux battery now and use a maintainer on it for cold nights (it doesn't get driven everyday either). Keep in mind when doing this, the car needs at least 3 driving cycles to again become emission test ready! Does anyone think a low or weak aux 12v battery could cause these wild SOC excursions on the HV system? P.S. there is no burning or corrosion at the Vsense harness connector to the batt ECU. No burning smells either.

 

Also I've sent email to I believe Ted at NPB with no reply, so they must've gotten layed off???

 

Hi 2k1toaster, how many units have you sold? I see that the website still says the price is $1600 but it seems like the price has gone up to $1789? Any chance it'll go down anytime soon or it will only go up from this point? thank you.

 

I would definitely attest to properly torqued terminals. In December, 5 days before a 90 mile trip for xmas I kept getting the triangle of death. Throughout the work week it kept getting more frequent. So I took a day off to replace a module I had purchased months in advance. Worked like a champ, for two months. The triangle came back. So I replaced another that had low readings. My pack only worked well for a week or two. The triangle came back. Had to keep clearing engine warnings while driving just to keep going.

I did notice in the Dr. Prius app that the Internal Resistance was going way high, for all the blocks. It had reached 30 and even higher to turn to the color red. Even though the voltages seemed okay, after a while in the red I'd get the triangle again.

So I found an old IN LB needle torque wrench in the my dads old toolbox, probably off by 2 or 3. I loosened what I had done previously and the wrench only went to around 15-20 IN LB. I had previously tightened all 60 nuts with a drill at a random torque number. They seemed fairly tight at the time.

So I torqued all the nuts to about 55, ya maybe a bit over, but I've seen that post someone experimented and found over 100 is when it starts ripping things. So anyway, it's been great for 3 months so far, even on a 90 mile trip.

I'm patiently waiting for my NPB I pre-ordered on March 8th. Only 2 more months to wait until another possible delay, since my shipment should have been May already. At least I still have a module that's probably still good due to a faulty torque install.

Oh ya, my gen2 has over 170k and still on my original battery. So far just 3 modules swapped out.

 

Good news, everyone, Shanghai is reopening from lockdown. So hopefully we'll have our batteries soon.

 

Hey, have the batteries shipped yet? Your store states the next shipment will be 8/12/22, but I haven't received any notice yet if my order from March has shipped. Thanks.