Charge time

Why do you think the average laptop battery deteriorates fairly quickly? (or cell phone battery for that matter)

 

Is three years quickly? That's how long my cell batteries usually last, and they get a lot more abuse than the 25% - 85% SOC that Toyota limits the PiP to.

 

Ya, I think that's fairly quickly. Sure as heck want my PiP lasting a lot longer than that.

Also, if you were to do battery testing every month from the day you got your laptop and use it like most Americans do I believe you would notice a pretty significant and steady drop off fairly early in its life.

Personally, my goal is to have next to 0 deterioration for a long time on my PiP. Even if I have to burn a couple bucks of gas, that is well worth the potential thousands I may save upon resale.

 

> Even if I have to burn a couple bucks of gas, that is well worth the potential thousands
> I may save upon resale.

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Interesting. Potential thousands? Because the battery is degraded? When I traded in my old car, the dealer just looked at it and put a thumb in the wind. I suspect you could get the battery health out of the OBD II parameters, but it would take a bit of effort (and time to charge the car). I would suspect the dealer wouldn't run that test, but perhaps your dealer was smarter than mine (and my old car was conventional, so battery isn't relevant.)​

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But it seems like we are all talking without any hard data. It sounds like there was more language in earlier versions of the manual -- mine (a 2014) just mentions reducing battery degradation in half of a sentence (with the other half about off-peak energy use.) It would seem to me that number of discharge cycles is far more significant than storing for the dozen hours it sleeps in the garage -- and we are still charging it up to 80% anyways...​

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I suspect this is concern without cause.​

 

Because especially until fairly recently, most batteries in consumer electronics devices were allowed to use the entire available range of charge, which means that they are frequently discharged to zero and rapidly charged back to 100%. It is my hope that in the relatively near future as battery life becomes less of an issue, some devices will start to change that behavior.

Sitting at 100% charge is not the ideal position for a li-ion battery to be, but I'm mostly worried if it sits there for days, weeks, months, say like a laptop that is always plugged in. I use the charge timer for my car sometimes - but only when I'm certain that I'm not going anywhere else that night.

 

I give up. I'm clearly not changing any minds.

 

you changed my mind, i'm gonna leave mine plugged in all the time now.

 

I've got the same mind I have always had.

 

No.
But then about the worst thing that will happen is that I have to buy a second battery (~$50) for the laptop sometime in the 3-5 years lifetime of the device.
Or I may have to suffer through a year or so where the laptop works well but the battery doesn't last long so I have to plug it in more.

When/if a plugin hybrid car battery goes bad I may need to replace it at a cost of several thousands of dollars and/or get a lower range for years, thus using more gas instead of electricity.

I'm not really sure that charging to full (85%) and letting it sit that way (for 10-15 hours instead of 1 or 2) is a big deal or not. But the end consequences are much larger in scale than anything that has to do with a laptop of phone battery.

Mike

 

There many different variations on LiIon battery chemistry, like which other elements are used besides lithium. So it is quite plausible that Toyota has found ways to modify the behavior of the batteries in its cars.

 

They haven't. They extend battery life by limiting the depth of charge and discharge. If they had a better chemistry we'd know about it, believe me. As for leaving it at "100%" for a few hours, I'd only worry about that in blistering hot weather.

 

Looks like an even split on each side of the fence. There is not enough data yet IMO to say one or the another. I've got 10k EV miles thus far and no discernible degradation. At this rate, I will have >20k EV miles on my PiP's 3rd year. That'll be approximately 1800 charge cycles. Apple says my iPhone will retain up to 80% capacity after 1000 charge cycles. I'm already looking pretty good.


iPhone ?

 

So I have started using the timer, as recommended in the manual. But it seems as if it ALWAYS rounds to the nearest hour. Am I misusing it somehow. If I set it to start at 7 am and stop at 8:15, it seems as if I need to press the "ROUND TO NEAREST HOUR" button to get the timer to work. But then why would they allow minutes at all? Makes no sense.

My goal is to try to get it about 85-90% charged since I live atop a 750 foot hill...

 

I use the timer with minutes, so that works. It is not intended to be set as two discreet times like you seem to be using it with a specific start or stop time - it is either or - either you set a start time or you set a finish time.

I'm in the same boat as you living on a hill and I tried that trick for a while but unfortunately the timer isn't very smart so it didn't work reliably for me. If you set a finish time, say 8:30AM it does not take into account the starting level of charge, so it always just starts about 2.5 hours before the end time. Maybe it'd work if you always return home with no charge, but I don't so it just wasn't reliable.

 

OK. That explains a mystery, so thanks. Since checking it manually every few minutes is too much trouble, I guess we will just live with the annoying fact that the engine will always start on the descent. A daily trip for me is: 6 miles to nordic ski area. Ski. Then home. And route is hilly in middle, as well as the 750 rise to the house at the end. I am learning that doing the first 6 mi in HV and leaving the miles in the battery for the return trip gets me almost all the way home, and with a higher final number than the opposite, say. That is, if I can get the return trip done with all EV (or close) that works better than using the EV up first. None of this is huge, but one can spend time trying a variety of strategies. Going down the hill in neutral is too dangerous, etc.

 

Hmmm.... I guess "danger" like "beauty" is in the eye of the beholder. I've coasted downhill in neutral a few times in the past (never in a Prius), but I have no desire to ski. I mean, c'mon, at least a car has brakes! Just kidding!

 

And this is a killer for batteries because discharging always produces a lot more heat than charging and then most people do not allow their battery to rest before recharging it. Always a good idea to have a little buffer before recharging right away even if it means using the timer to have the car wait an hour before recharging it.

 

There's a lot of outdated advice still floating around. Few, if any systems trickle-charge anymore. They will eventually destroy a battery if left on too long. Most charging systems continually test the battery and apply current as needed, therefore the best practice is to leave them connected to the charger when they aren't being used.

I'm mystified by the message on my Samsung phone, which appears when my battery is charged, saying "unplug the charger to save power." What power? I have measured the current myself, and there is zero current draw once the battery is fully charged, in fact it's that way for all my electronic devices. I suspect that the engineers at Samsung had less of a say in the matter than the PR people.

 

Concurring, with a bit more info: While it was common to trickle-charge nickel-based batteries, that absolutely does NOT apply to lithium-based batteries. Even trickle-charging a full lithium-based battery can result in heat+explosive-gasses = fire. The battery monitor app on my Droid reports the charge rate falling to zero when the battery is completely charged. But my Droid also has that silly "unplug the charger" message; it is probably an Android thing rather than Samsung or Motorola.

And on the PiP, when charging is complete, the mains are disconnected from the charger by a relay in the EVSE when charging is complete, so the charge rate is zero.

 

The wasted power is in the transformer. Some newer ones are pretty good at having a very low power draw even when nothing is plugged in. But others aren't. You can tell by just touching them and feeling that they are warm long after nothing is plugged into them. Most are about 0.5 to 1 watt...but I had one drill charger that consumed 5 watts when nothing was plugged into it....yes that is 44 kwh in a year that I maybe had used 5 or 10 times for a few hours.

Hence, we have products like this:

Amazon.com: Belkin Conserve Socket F7C009q Energy-Saving Outlet: Electronics


Mike