Battery Vehicle Society

There have been so few gen2 traction battery failures that all one can reasonably say is that the batteries last the life of the car (so far). Ditto for motors. There are statistics floating around on the US Prius forums somewhere.

The last figures I saw for Toyota replacement batteries was I think somewhere in the£1500-2000 area, but just ring a Toyota agent and ask. Used they're around £300-400 I believe. If you get one from a recent car thats only had a front end crash you're likely to get a good one.

I've considered adding extra packs like Nikki (aminorjourney), but our mostly extra-urban driving would probably mean little benefit. If we lived and drove in an urban area so speeds were nearly always below 30 it might be different proposition.

I have a Y-reg Prius classic (forgot the model number) and it has done 140 kmiles and still returns 60 mpg indicated at 65 mph on a reasonable Motorway journey.

TBH it seems like it will go on for ever.

Battery life seems very long indeed now, although there were some problems with early cars.

The first Prius, the NHW10, had a significant number of battery problems, but as this car was only ever sold new in Japan few of these are documented on a worldwide basis. The second Prius, the NHW11, had some very minor problems with battery pack sealing, but generally the batteries seem to last the life of the car. By the time the third Prius, the NHW20, was launched Toyota were confident enough to give the battery (and whole hybrid system) an 8 year, 100,000 mile warranty. I've heard of NHW20 models that have topped 200,000 miles with no problems, so wouldn't hesitate to suggest that the hybrid system is probably one of the most long-lived and reliable parts of the car.

The fourth Prius, the one that's just been launched and that is confusingly referred to as the 3rd generation by some, seems electrically very similar to the NHW 20. As such I would expect it to have similar reliability and life to the NHW20 model that it's replacing.

Overall, the later model (NHW20) Prius only has a few minor recurring problems:

- The alloy wheels are appalling. I had two sets replaced under warranty in three years, due to really bad corrosion.

- The original 12V housekeeping battery can have a relatively short life if the car isn't regularly used, as it is of small capacity and there is a modest housekeeping load drawn from it when the car is parked up. There is some evidence to suggest that higher quality/capacity aftermarket batteries last longer.

- Brake pads may well outlive brake discs at the front. My Prius was showing just 40% pad wear at 60,000 miles, but 70% disc wear.

- There was a steering recall on many NHW20s, so it's worth checking this has been done in the service record.

- Steering motors (the steering is electric) can develop a fault with the position sensor. It's relatively simple to replace, plus there is, I believe, a cheap DIY fix that's been discovered by some of the ardent Prius tweakers.

- There were some reports of a connector sealing problem on one of the sensors that occasionally caused some warning light indications. There's a simple Toyota mod to add sealant to the connector which stops the problem.

- False system warnings can occur very rarely. These often go away after a few car re-boots, as they seem to be caused by the odd signal glitch.

- Paint chipping on the front and bonnet area is common, due to the shape of the car. I doubt this is any worse than any other tear-drop shaped modern car though.

Jeremy

Hi,
I am relatively new to the forum and i have completed a diy install of an Enginer PHEV system.

It is a 4kwh lithium battery pack using real force 20ah cells of similar layout as the A123 cells, they are pouch cells housed in a stainless steel enclosure.

My prius is a 2004 gen2 with 65k on the clock, and before the mod was returning 45mpg in a hilly area of the south wales valleys, the hills for sure do hurt the mpg`s.

With the kit fitted i am now getting an average of 65mpg. I have done some tests on flat ground and the mpg is considerably better, in the high 70`s mpg, the hills where i live hurt the mpg alot.
I fitted the kit myself with no help from anyone, its not that difficult to do, but i will say its not a plug and play and forget bout it system, it does require some knowledge on how it works and how the batteries perform.

I dont regret buying the kit and i am seeking further mods to allow longer electric only mileage. It was only fitted in november, and i canaready see the benefit of the warmer weather, i am hopng to be in the low 70`s mpg as the batteries start to perfom better as they get warmer temps.

My ideal goal is to be totally electric, the imievs are starting to show a reduction in price, bt as still over 10k too far ro me to go cost wise. May look into a conversion of an audi A2 with engine failure, lifepo4 batteries are fcoming down in price, and are starting to become available as used packs, so a diy ev conversion with lithium may be an option in the near future, the prius will then be sold on to another hobbyist to enjoy the phev experience.

Thanks.