Max EV range on 2017 and 2018 Prime

i'd be shocked if they didn't. all lithium batteries lose the most capacity in the first few years. it looks like you have done very well!

 

As you saw on my thread, what you're seeing is pretty normal. At least very similar to mine.

 

My 2017 prime is currently 40K miles. Now I can only drive 20 miles with full power, and the battery is attenuated by 1/3.

 

My 2017 prime is at 35K life time miles... I am getting around 38 miles EV range

 

2018 Prime Advanced
record: 42 ml on ideal roads ( no interstate, min streetlights, pretty much hypermiling)
routinely >35 ml
@<70K I can barely get 27-28 ( no AC , but occasional fan on) HOWEVER, do get occasionally ~31-35 ml on that ideal road, don't understand HOW
Florida, so temp not a factor ( I'm reporting without AC)

 

there are many factors affecting ev range

 

Hard to tell without systematic data, but if I had to guess, I'd say just under 10% for me.

 

My 2017 started out with 28 miles. It slowly grew to 34 miles over the next 4 years. I suspect this was due to my driving efficiency going up (I am now at 4.5 miles/kwhr) in combination with never seeing a recalibration.

About three months ago I drove it down to zero battery capacity; that (I think) did a recal and now it's at 26 miles. So I suspect I've lost about 15%, with the car only reporting a few percent change due to the higher estimated kwhr/mile.

 

How do you drive a prime to zero capacity?
All Toyotas limit the bottom end

 

4.5 miles/KwHr is quite good and I can only accomplish this during the summer months. Down to 3.7 miles/KwHr here in the winter months now; but the guess-o-meter can't be trusted for accurate information. It's a best case estimation. Using a GPS unit on a flat stretch of highway; I've found my speedometer was 2.5 mph faster than actual distance traveled.

 

As @bisco said, it's not possible to run a Prime or any other Prius battery down to zero (unless you jump through some very special hoops). If you look at your trip meter's mi/kWh, and it matches what you had been getting and you still have less range (real range, not the made up number on the GOM), then you have lost capacity. But chances are, you'll see that you're getting fewer mi/kWh than before and therefore less range.

 

Battery degradation is normal. Keep the battery around 30% charged when undriven to minimize it. Avoid fast acceleration, fast deceleration, and high speeds in the EV mode (all resulting in high battery currents (high discharge/charge rates)).

For a new battery, it should take 6.25 kWh with Level 2 and 6.90 kWh with Level 1. Your 220-V charging is close to Level 2 but not exactly Level 2; so, I would expect ~ 6.4 kWh. It sounds like you lost ~ 14% capacity, which is a little on the high side. Keep the battery around 30% charged when undriven and avoid fast acceleration, fast deceleration, and high speeds in the EV mode to minimize it.

 

You drive it until the car decides the battery is "empty." That generally happens via a combination of coulomb counting and voltage measurement. The voltage measurement is important because coulomb counting assumes a given amount of storage in the battery, and that amount degrades over time. Hitting what the car considers "bottom" allows the gas-gauge algorithm to calculate a new storage capacity, and from then on it works with that.

Hence, the first time it hits that point after not hitting it for a while, you could see a sudden change in capacity. I am assuming that's what happened here.

My first hybrid was a Honda Civic hybrid, and that had an algorithm that would discharge the battery completely, then force a full charge to do a hard test of the battery's capacity. It was annoying when you were trying to plan to use its tiny battery capacity efficiently for hills and the like. (You wanted to be near full at the bottom of the hill and near empty at the top to take best advantage of the hybrid system.)

Heck, all battery systems do that, period. For lead-acid systems it's generally a mistake to go below 50% charge for any length of time. Li-ions are way, way better, but you still can't take them down to zero, because that will destroy the battery. All EV li-ions have a BMS that will physically disconnect the battery when you approach a few percent remaining based on voltage - and the car's ECU will tell you you're at zero range remaining (and start the gas engine) way before that point.

 

2017. Still getting 30+ miles in the summer. Winters are rough in Chicago and happy to get ~17 miles range.

 

Gotcha. You meant zero wall charge

 

On this subject about mileage, has anybody even priced or replaced their battery so they could get more miles like when the car was new? Our battery has really taken a hit. We have had this car since it came out in 2017. Our miles for the last 6 months has dropped quite a bit, at least during the winter months. I don't think it will be much more even in the warmer months. My husband is curious if replacing that battery would be better.

 

Replacement would be very expensive.
Without specifics, it is unlikely your battery has lost much capacity

 

If (when?) you seriously consider swapping a battery, it might be possible to (greatly) increase the capacity. There are new batteries coming available slowly. As an example of related developments, older Prius hybrid batteries (not the PHV/Prime) might be upgradeable using NextPower's Project Lithium battery (refer https://projectlithium.com/). While I don't know of concrete examples available today for PHV/Prime, one enthusiast has an exciting project for Gen 1 PHV/Prime (refer quote below), but which still has a long way to go before fruition and availability for the general public. Something similar should be adaptable for the Gen 2 PHV/Prime.

As pointed out already, cost would be an issue.

 

Is replacing a still functioning battery, thus not warrantable, for ~$10K out of your pocket really worth the cost for gaining so little?