Early Hybrid battery failure!!

The best thing I can suggest for long term battery health is temperature control. Keep the battery cooling fan perfectly clean, and use your air conditioner to keep the cabin cool.

 

what's wrong with those voltages?

c has a rep for shorter battery life, imo

 

+1 clean the fan screen


Why are you worried about it?
Do you have an error code or did the dealer give you a bad battery report?
(The voltage "problem" shows up as an unacceptably large variation in cell to cell voltage.)

Rob

 

I do not know that you, the OP, have a bad battery. Clean the air vent yes -- even better remove enough rear interior so you can get to the HV blower fan and disconnect, remove and give that a good cleaning. You can also google for how to tell the HV fan to come on at a lower temperature, I think. Finally, I would at the least buy the Dr Prius app (disregard the free version info), pay the $8-10 to get access to the two battery tests and do them both. The one where you sit in your cabin for 10 min drawing a lot of current will give you a sense of how serious your issue is. If it hasn't thrown a red triangle, it may be fine. I rebuilt my battery pack and posted a wiki here about it. If that's not your game, you can pay a lot less than dealer prices for a perfectly good rebuilt pack. Given the newness of your HV battery, I would suggest not saying goodbye to it, instead just having someone replace the bad modules, being sure to rebuild the pack in a nice balanced way, and to clean the copper connectors when reinstalling.

BTW, my rebuilt pack has about 3,000 miles on it so far and seems ok, despite me not really understanding how to balance the internal resistances of the modules. Initial Dr Prius test showed 104% and now after 2500 miles it's showing 95%. We'll see how things look in a year and then every other year. Hoping for 50-75,000 more HV miles before pulling the pack again...

 

Are you in the United States?
If you are in the states , your car maybe covered for battery replacement,8yr/100k mile in some places such as California. You can try touching base with Toyota for clarification of what is or is not covered. Maybe they will cover if if the battery is diagnosed to be failing/bad by a dealership.

Like others have already mention, try to keep the battery cool. I am currently in the process of reconditions/ rebuilding a Prius C traction/hybrid battery after getting a replace hybrid code. When I removed the battery from the car the mesh screen on the fan was plugged with a thick build up of lint and dust. I am pretty sure this is why I am having to replace 10 modules on the traction battery. This particular car has a bit over 100k miles, so not covered under warranty. Your’s is well below that, so again if you’re in the US, best to contact Toyota USA and see what they say.

 

Are you addressing the Original Poster? His info says Jordan. Also in his info: he hasn’t been back since posting in this thread, October 6th, 2019.

 

I’ve been to Jordan. It’s hot there. Heat kills batteries extra well...

 

YeaH, I was. Things on the net stay in stasis for much longer than out here in the real world.

 

Do you think it could be good the leave the hybrid battery fan to run all the time? this is what i do with the OBDLink scanner, i put the hybrid battery fan at max speed, all the time, with the A/C on, the battery stays very cold. Here in Puerto Rico the weather is really hot, i want this battery to last, even more now after i had to replace the expensive brake booster assembly and brake pump assembly.

 

I have to think that Toyota has considered a few things in designing a thermostatic control for the fan speed.

What I don't know is if the system chooses lower speeds to preserve fan lifetime, or if lower speeds is done only to lower the cabin noise.

Said another way:I think any action resulting in lower battery temperatures is going to work in your battery's favor... I just don't know if it will cost you an extra fan to do it that way.

My wife and I already have a general preference for driving with windows up and AC on, so we aren't doing anything extra.

 

I would say it is ‘kind of’ good to leave the hybrid battery on all the time.

The battery computer ‘samples’ the best coming cabin air temperature (tiny bursts of the fan to do this), and only draws air with the fan if the cabin of the car is *colder* than the actual battery. (I’ve experimented with this to figure out the algorithm).

What you want to avoid is damp getting into the battery. Damp battery can result in faster corrosion on the electrodes, bus bars, engine computer etc.

If the battery is colder than the car’s interior, then unless the air in the car’s interior is 0% humidity, condensation *will* form on the battery (and to some degree the electronics as the battery isn’t fully airtight).

You want to avoid having the battery fan running when the battery is cold and the interior is warm (for example, starting out on a cold morning and using the heater to heat the cabin).

Keeping the battery cool is helpful, and using the AC means the cabin will be cooler and drier. I would still be tempted to only put the fan to ‘max’ after some driving (and even then, the battery cools down a lot on highway trips at constant speed, and heats up a lot with stop-start driving. Cleaning the cooling fan and filter etc will help;

an OBD app that dynamically controlled the fan taking cabin temperature into account, and which had a ‘maximum’ setting - which cooled the battery at ‘maximum’ fan speed (as long as the cabin air is cooler) would be great.

 

This is an interesting thread. While most of us here are not auto/battery engineers, the designers of the Prius HV battery system probably didn't live in the hot and humid places that some of us live with Priuses.

If anyone is going to be doing a HV battery removal/repair, it would be a good time to:
- clean the vent that leads to the HV fan (consider installing a light filter material when putting the vent cover back in place too)
- remove the HV fan, disassemble and clean out the gunk on it
- re orienting the 3 or so battery sensor wires from the edges of the battery pack to the center. The middle of the HV battery pack heats up the most - and is moved to the outside during battery repair - and so by locating all censors in the middle, the fan will be turned on earlier.


-

 

Maybe the car decides to run the fan when any one sensor reads a high enough temp?

 

I like to think that this is the reason they installed a variable speed fan with a thermostatic driver. There's lots of stuff in a typical car that is engineered to handle environments hotter and colder than the designer's cubicle.

They might not have made it perfect but I've never thought it was lacking to the point where it needed my intervention.

 

I don't know the answer to that. Does anyone here? Ouch - my word 'censor'. Ah for the days when our secretaries typed all our online missives carefully and thoroughly!

 

Well, that's true (I hope) but I did notice (and others have posted about) the interior modules of the HV pack getting more heat/lack of air related damage...

 

I’d speculate, that Toyota’s engineers specd 3 sensors, one in the middle and the other two towards the end, to cover any and all scenarios. Who knows; maybe one of the cells out towards the end of the pack might act up, overheat. Likely never, but still, I’d think one sensor at the middle would be enough to activate the fan and more don’t makes it turn on sooner, or run at higher speed.

 

Yes, this is precisely what I mean by "not perfect." I'm all for taking action to protect value; I just don't see much value being protected when you're talking about the last days of a car battery's life.

If the battery in our car lasts 3900 days instead of 4000 days because the middle got warmer, I'll cheerfully accept that.