EV charging only to 28 miles, dropped from 32-33 miles

Very good! My long-term average is 4.6-4.7 miles/KWh.

 

When Tesla did this to some older cars, some people got outraged. I think you should follow their example, and sue Toyota.

 

Haha... Yeah, not likely...

 

There are multiple things going on. Long term degradation is a different effect than temperature.
A brand new battery that is cold will take less charge than one at 70-80F.
Warmed back up it will charge like new.
Over many charge/discharge cycles the battery will take less charge and never recover (at the same temp).
Over many years the battery will also show degradation even with moderate charge/discharge cycles (at the same temp)

Charging and discharging, avoiding fully charged (100%) and discharged (0%) give the battery less degradation as well, trading longevity for smaller range.
These are all well documented characteristics of the various Li-ion battery chemistries

Mike

 

Yes.

What I’m seeing is not likely temperature-related, and it’s borderline as to whether the battery cells themselves have physically degraded any appreciable amount in just ~3 years. Since it “bounced back,” almost certainly at least some of it is simply charge-management programming/heuristics.

BTW, I said earlier in this thread that it bounced back to charging 5.5KWh now. Just for the record, it’s actually more like 5.7KWh.

 

different ~ yet inextricably intertwined. Reason being, (especially in an air cooled plug-in) a plug-in may easily get charged on a 100° day ... the capacity losing effects of charging increases via heat. Most heat on charging is at the top of capacity. If you've discharged on a hot day (which generates Heat) then it sits charging on 130° asphalt to charge, & temps go up higher as higher capacity charging is allowed ... then over long term - said scenario will increase capacity loss.
The best example of this was the first iteration of the Nissan Leaf. The record for NOT losing the 1st percentage capacity bar own the Leaf's dash was over 4yrs & 70,000 miles. That occurred on Northern Coastal Washington State.
Owners discharging & charging in Vegas could lose 3 capacity bars in one summer. (We opted in to the class action against Nissan.) Moral of the story was that keeping a traction pack cool will increase longevity.
.

 

Well, it's April now and my range is only going down. I'm at 25 miles now (on a full charge). Anyone else experiencing this?

 

Mine varies daily from 4.0 to 5.6 m/kWh depending on weather, speed, and traffic conditions.

 

GOM range is strictly based on your recent EV drive efficiency. Check your Eco Log for your past few months EV efficiency (miles/kWh). If that number is ~4.5miles/kWh, then your GOM is very consistent. You can increase GOM range by driving EV mode more conservatively to increase average miles/kWh, but it takes some patients to start seeing the results.

 

Mine has never recovered either and with gas down below $2/gallon, it's really not financially worth it to charge the battery.

 

out of curiosity how many kwhrs did your car use from the wall to get a full charge when new versus today?

Have you been tracking your dash efficiency metrics?

 

efficiency is different than voltage capacity.
.

 

Naturally. I was only responding to the range question. And that's exactly my point. Range depends on efficiency AND capacity. I check my capacity at least once per gas refill (2-3 months). It's staying around six and a tiny fraction kWh from depleted depending on how far into the HV portion I've dipped.

 

At the end of the day when I charge my 12v car battery I don’t end up with the meter saying I added 2 miles.

batteries don’t charge miles
They charge kwhrs

tires, inflation, brake drag, temperature speed, driving techniques, heat all affect miles and gas mpg even if the amount of battery capacity is the same.

Discussing miles is almost irrelevant except maybe to find a dragging brake or under inflated tire.

 

Unless there's an underlying mechanical issue, it's STILL ~46-47 degrees in Pasadena CA in the early morning this week....

This temp is "Roughly" 30 degrees away from optimal battery performance.

Battery University:
"A battery that provides 100 percent capacity at 27°C (80°F) will typically deliver only 50 percent at –18°C (0°F). The momentary capacity-decrease differs with battery chemistry."



Rob43

 

Good point, I haven't been checking these logs (actually I wasn't aware the logs were kept). I'll look into them.

I did notice back in the days I would get a projected 33 miles range, the car would take in 6.5-6.8 kWh from the wall. The last few times I used it, I noticed it was taking in around 5.8 kWh. Now I charge at a public free L2 charging station (because I moved apartments) which doesn't tell me how much energy I've consumed. It could be lower, I'm not sure.

That's true, but I'm also referring to a sort of mean projected range. So it'snot just a one off reading, this is sort of the average figure. And my driving conditions do vary from trip to trip.

Good point, Rob but I would also say that my range didn't take this much of a hit the previous two winters I've had the car.

 

The "Guess O Meter" and the actual computer logs are two separate things. So far as you've pointed out, all of your info is based on the GOM. Once you start logging actual computer data at roughly ~70 to ~80 degrees F, that's when you'll have a more realistic idea of battery performance.


Looking forward to your results,

Rob43

 

well ya - because your 12v aux battery doesn't drive you down the road .... and if it did .... and its capacity was diminished to 6v - you'd go down the road a whole lot less.

zakleee - because miles varies. One needs Toyota's tech stream tool to measure cell voltage - to determine loss - not miles. But unfortunately, ifaik, Toyota, like most manufactures - doesn't warrant voltage/capacity loss. So - if in a couple-few years after yer Prime drives of the lot new, your prime doesn't take as big a charge? The Service Center - if they'e polite? They may tell you, "C'est la vie"
.

 

Check your tire pressure recently? It will fluctuate with the temperature, and air trickles out over time.

If it is still cold there, I wouldn't expect warmer weather range until it actually gets warm.