Can you drive too little?

welcome!
yes. but the hybrid battery will be fine. the 12v can suffer, if you don't drive often enough. 5k a year is fine for a prius, but doesn't make a lot of sense unless you really want one.

 

Get a 12v trickle charger AND what's called a grid charger for HV battery.

 

i suspect the dealer is hoping to sell her another car.

 

I bought my 2013 Prius model 3 new in Aug. 2013 and I only have 11,500 miles on it so as you can see I don't drive it much. The Hybrid battery is just fine but I just had to replace the 12v battery because I don't drive it enough and now I keep a Battery Tender on it during the week.

 

Pearl saw about 7000 km per year and still has no problems. Pearl S gets 5000 km per year and has yet to show any problems. The traction battery will last -longer- with low miles. It "wears" from time -and- use. Cut down on either and it will be better.
Unlike a lead-acid battery NiMH won't degrade if left unused. It will -slowly- discharge, but it takes more than 6 months of no use to cause worry.

However, to actually -pay- a Prius should see around 20,000 km per year or more. The more it sees, the better the economics. You have to cover the alleged "hybrid penalty" (a bogus "alternate fact").
Some of us just like the technology.

 

However.......they juuuuuuuust happen to have a bunch of non-hybrids that they would be very happy to make you and/or your friend a good deal on?

This is either a case of incompetence or sleaziness.
I wouldn't have to know which one to avoid this dealership with extreme prejudice.

If you cycle the car enough to put 5,000 miles a year on it, then there's no reason to suspect that the car wouldn't thrive under those conditions.
How many hypercommutters out there would absolutely LOVE to get their mitts on a 10 year old G3 with 50,000 miles on the odometer in a few years???

Unfortunately, there is one inconvenient truth out there for the 5k/yr driver.
Priuses are more expensive than some other non-hybrids.
Prius owners do not like to hear this, and when it comes up then out come the long knives and bar graphs and pages and pages of options and package comparisons but at the end of the day you simply cannot build a hybrid for the same price as a non-hybrid.

So....if I were a very low mileage driver I would lean away from hybrids and new cars altogether but not for any other reason than I would not be logging enough miles to justify the expense.

 

When gas prices were $2.50 in CA, I bought my Prius. I figured it would take 100,000 miles to make up for the premium over a regular less expensive vehicle. Whether I drive 5000 miles a year or 20,000 miles doesn't matter. As long as I keep the car past 100,000 miles I'll save money over the regular car.

So the dealer can be right 20,000+ a year will save a lot of money. 5000 miles a year not so much and in my case not at all as I don't plan to keep the car 20 years. But consider I was going to buy a Versa which is half the Prius cost. If a shopper was comparing a Camry and a Prius, then there is no premium. They cost the same so even if they drive 1 mile a year, a Prius would save money over a Camry. It all depends on what the other car is.

The hybrid battery won't be ruined though if driven 5000 or even 2000 miles a year. The key is any car, hybrid or otherwise needs to be driven regularly to keep the fluids moving, boil off any water that may have condensed, keep tires from flattening, keep brakes from rusting, etc, etc.

My rule of thumb has always been to drive the car up to operating temperature every two weeks. I recall my PiP manual stating to fill up half a tank of gas every 6 months. So the lower limit for driving per year is one tank of gas or 500 miles or 10 miles every 2 weeks. Take that with a grain of salt.

 

I drive 22k miles a year its our work horse prius

 

We're working at it: maybe 6000~7000 kilometers a year now. We do occasionaly have a good drive, from North Coquitlam to Downtown Vancouver, or over to the North Shore. The car will sometimes sit 3~4 days; I've gotten into the habit of keeping a CTEK plugged in constantly. Once it's done charging it's ok to be left on, just trickle charges.

 

however, the HV battery will die at about 12 years of age (i'm guessing) and the owner will benefit little from hybrid with so few miles on the spent battery.

 

That is an opinion I don't share given the plethora of Prius older than 2005 still on the road on its originally battery including my own. But if you believe the HV battery will die at about 12 years, then agreed, OP wouldn't benefit much from a hybrid.

 

I would really love a more definitive, long term perspective on this question.

My cousin has had their Prius for 20 years and are still on the original big battery. They drive 7500 miles/yr; same as us. We just bought a 2014 Prius V with 78,000 miles, and hope to enjoy long battery life by continuing to drive no more than 7000 miles or so/yr. But… we are not in the habit of driving much day-to-day. Our previous car would regularly sit for a week or more. It never occurred to me that things might be different with a Prius.
So - my questions:
(1) If our driving is irregular (week+ here or there with no driving), which, if either, of the batteries will suffer?
(2) if so, would a battery tender help with this?

Thanks!

 

I don't know about the gen3's but on the gen4's the manual states to run the car at least every 60 days, enough to cycle the battery down and allow the system to recharge the traction battery back up to the half-way point. It sounds like you'll have the opportunity to do that, so your giving that traction battery the minimum care it needs, though batteries tend to do better the more they are cycled.
The other issues with batteries is heat and to a smaller extent cold. If that Prius spent most of it's 78K miles in the hot desert SW, that would shave a lot of life off that traction pack. IMHO. Those gen3's do blow head gaskets, mostly above 120K miles, preceded by early cold morning start up misfires that disappears after a minute of idling and very slow lost of coolant.
The battery tender will keep the 12V battery from dying, so it'll start up on your infrequent trips.

 

We’re driving once or twice a week, about 3k kms a year now. It’s a 2010, odometer at 102k kms, garage-stored, very well maintained, 12 volt battery (over 8 years old and load-testing like new) on a smart charger virtually all the downtime.

The drives are usually good length too, engine gets a workout. If we need a few groceries we’re fortunate to have walking distance stores. More or heavier shopping, we’ll try to consolidate with one of the longer drives.

the hybrid battery seems fine, behaving no different over the years. I’ve checked it with Dr Prius app a few times, but not for a while. Should do that again.

 

A Prius that doesn't get driven a lot isn't necessarily bad for the battery until you get into really extreme disuse, months at a time. That kind of disuse can shorten the lifespans of both the 12v battery and the hybrid traction battery.

The kind of usage you're describing isn't going to be hard on the traction battery, but it may call for a tender on the 12v battery.

There is a second part to the story:

Although your predicted 7,000 miles per year won't actually hurt the traction battery, you won't really be getting your money's worth either.

The hybrid batteries have a finite lifespan whether you are using them or not. At 7,000 miles per year, you'll wind up paying more per-mile to operate this car than you would to operate a simpler gas-only car.

This Prius may still make sense to you for other reasons, but it's not going to save you any money when used that little.

The "escape hatch" is to get rid of the car before it needs any of the expensive Prius-specific things (including traction battery replacement) that seem to happen between their 10th and 15th birthdays.

Good luck!

 

Don't let anyone scare you about the Prius.
Every care has its issues.

You probably should charge the 12v battery every few months since you aren't driving much.
The 12v battery doesn't have a chance to get a full charge. You can charge it from the fuse box
under the hood.