ev battery lifespan

Worthwhile question!

I charge our 2017 2-3 times per day, although “to full” only about 1/2 of the time.

Mine started with a GoM (projected range) of 32-35 miles. It stayed there for around a year the plummeted in three distinct steps down to a low of ~25 for 8ish months. It then crept back up several months ago back to ~30.

The big drop occurred after a several-month period of time in which is charging it up at the local mall (cheap!) and leaving it mostly-charged overnight. I’m pretty sure the computer started fearing for battery longevity and increased the “top margin” of the battery (the highest point it charges to).

In short, use timed charging as much as possible, and we’ll probably see an 80-some-odd percent 10-year life. It’s not liquid-cooled, but at least it’s forced-air-cooled.

 

No change in the charge capacity in two full years, 35K miles with daily charge. If anything I am getting more EV range this summer than the first two due to the way i manage EV/HV.

 

Same drive 2 years later, no change.

 

Coming up on 2 years with my wife’s Prius Prime. We now have over 15000 miles, %96 EV. We plug it in a dedicated 110 outlet every time we park it at home garage, leave it fully charged overnight and have not noticed any change in EV vehicle projected miles. Still 28 (projected) EV miles in the cold Syracuse NY winters and 38 EV miles in nice summer, ramping up and down the other two seasons.

 

Ive got ~19k on mine and haven't noticed a decline. I get about 33mi/ charge.

It was higher when I used back roads to get to work. But ever since i put OpenPilot on it, I take the highway and let it drive up to 75mph (high speeds use a lot of power... that dang v^2 drag!)

 

EV range isn't the best metric for battery degradation. Keep an eye on how many kWh it takes to charge it from zero EV range. Mine is still about 6.8 kWh although I've only had it 6-1/2 months. I recently had one just over 7. I don't keep precise numbers, very often, though.

 

GoM changes depending on how you drive, so it's not a good indicator. Keep it fully charged and if you drive it till almost zero, make sure you charge it right away.

 

First sentence, spot on.
Second sentence, ... Nooooooooo! That's the opposite of what the manual says and is probably THE worst thing you can do to your battery -- especially in warm weather. Don't charge it till you need it. These batteries like to be stored at a relatively low state of charge.

Interestingly, iOS 13 now defaults to charging up to 80% and then waiting till just before you typically use it to finish charging. In other words, if you plug it in before you go to bed, it won't sit all night at 100% SOC. It's something they should have done years ago.

 

“Relatively low” might be reasonable, but best I can tell, these batteries are not best kept nearly discharged. Clipper Creek here 10 Tips to Extend the Life of Your EV Battery | ClipperCreek recommends letting them sit at around 50%. That’s probably somewhere around 10-12ish miles on the GoM.

But yes, I absolutely agree that you reeeally don’t want to keep them at full charge for very long! Best I can tell, keeping it “fully” charged overnight for a few months in a row caused the charging system to temporarily reduce the amount it let me charge temporarily down to about 22ish miles, and then only after several months let it go back up to 27ish (30 on the GoM).

I put “fully” in quotes above because, as with all (PH)EVs other than Teslae, Toyota maintains a 10-15% “top margin” that you can never charge above, to save battery life. They keep that top margin invisible to you (mine is probably closer to 15-20% now). Tesla shows you the entire range of the battery, and lets you use that entire range of charge, if you conclude that you absolutely must. Needless to say, they discourage you from doing so though, or not routinely at least.

 

It also states in the manual not to leave it fully charged. It says it's best to charge it up right before you use it.

 

Yes, when you switch from EV to HV either manually or EV auto mode or when you run out of EV range, the initial few miles HV run will be almost all on traction battery while the ICE goes through the warm-up. During this period even though you are on HV mode, the traction battery SOC will continue to decrease.

 

This is the reason it's OK to switch to HV at speed. The MGs take most of the load till the engine warms up. Once it does warm up, you'll see the instantaneous mpg gauge go well below 50 mpg while the engine repays what it borrowed from the battery and the EV range (if any) goes back to roughly what it was before the switch.

 

'Nuther thing. The throttle response is better in EV than HV. So when you or the car switch to HV, you'll probably notice you have to press a little harder on the "go pedal."

'Nuther 'nuther thing. As the battery approaches the state of charge where it was when you went from EV to HV, the rate of charge will slow down, so you'll see the mpg gauge climb back up toward normal and the battery level rate of increase will taper off.

 

Yes, I live in San Antonio, Texas and have experienced about a 25% drop in range after charging. I have been thinking about taking the vehicle in to have the battery checked since I am not getting the 25 mile range stated by Toyota. 2017 Toyota Prius Prime Advanced Plug in.

 

Welcome, George. Range isn't the only indication of battery condition. Traffic conditions, driving style, and weather will have a huge impact. How many kWh does it take to charge it from depleted now compared to when it was new? That's far more indicative of battery capacity than driving range.

 

Check your tire pressure if you see a fast range drop. I went from 25 to 18 miles EV. My tires lost air due to the cold weather. I was at 30 lbs pressure.

I went back to 40lbs pressure and I am back up to 25 miles on the freeway at 75 mph. Much more in the city driving.