Battery longevity driving right away from a cold start???

Would you rather wear out the engine at cold start up? The reason the battery is used more is so that the ICE can warm up. Use an engine block heater if you are concerned.


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Yes, it is designed to give the engine a break during warm up and use battery power initially. That is how it was planned to work. If possible, do not immediately drive over 30 MPH, so the HV battery can take the load off the engine.

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Others posted while I looked for my sources.

 

If you watch the charge rate on an OBD reader, you will see that the battery is being charged during warm-up, not discharged. The car will use the battery if you accelerate into the power zone, but otherwise it does not. The Synergy firmware is pretty smart about storing excess engine capacity in the battery.

 

It's being charged, but if you accelerate more than half in the EV range before the first minute of warm-up is completed, you'll discharge faster than you're charging. If the beginning of your drive involves accelerating to a point where the battery is quickly emptied, the fix for this is to accelerate slowly after starting, or give it ~30 seconds to idle before moving.

The car will empty the battery if you're in the power zone for too long, but a similar thing happens during warm-up.

 

No.....not unless maybe it is 40 below zero or so.

I'm beginning to think that there is something in the water causing OCD to be rampant.

It will NOT harm itself.
But if that really bothers you, just wait until the ICE comes on for it's warm up and then drive off; it won't use hardly any battery at all.

 

The C doesn't work that way. It forces the ICE to run to warm up and uses IT for propulsion while it is doing that.
You cannot even force it to use the battery above 5 MPH or so......if the engine is "cold", that is.

 

I have only used a Gen 2 and a v, in both cases, it runs the engine starting at 5 seconds after ready, but leans on the battery and really drains it during startup, the engine is not given big loads, it is just running. I would be surprised if the c did not use similar logic. The c HV battery is smaller, so may well drain so soon they need to use the engine sooner

 

It's not harmful to the traction battery aside from wear & tear from charge/discharge cycles.
However, the ICE is another story. I assume Toyota designed the mandatory ICE warm-up period for a reason, which probably relates to emissions and engine longevity. If, during the warm-up period the battery is drained to two bars or if you accelerate hard enough, the ICE will ramp up rpms past the warm-up level, for safety reasons (and so as not to drain the battery past the lower threshold).

Is accelerating hard during warm-up a less-than-ideal way to operate the C's ICE? Yes, or why would it purposefully exist?
Will it make a noticeable difference over the life of your C? No idea.

Do a cold start (could be up to a half hour (?) after the car's last use in hot climates) and accelerate somewhere between the EV line and the power line and watch how quickly the battery level drops. Do that from a driveway onto a 55 mph road and you'll go from 6 bars to 2 before you reach 55 mph.

The ICE isn't used as the main source of propulsion during the 1 minute warmup.

Simple tests:

1. From a cold start, accelerate slowly (within the first 30 seconds) to be within the "eco" range of the HSI. The ICE will sound/feel the same throughout the acceleration, and the battery will be draining. Yet you'll be accelerating, so you can guess where that energy is coming from. Once the battery is at ~2 bars, the ICE will increase rpms regardless of if it's completed the 1 minute warmup cycle or not, because you're demanding power and it's forced to deliver.
2. From a cold start, immediately (within the first 30 seconds) accelerate hard to within the power range. The battery will drain quickly and the ICE should quickly increase rpms. The C wasn't really designed for this, since it's targeted towards people who live in suburbs and cities and who do a lot of low-speed, stop & go city driving.

10 mph from a cold start, assuming light acceleration and sufficient battery level. However, as I said, the battery is used as the main source of propulsion during the 1 minute warmup, so even though the ICE is on, it's running at a very low idle level.

Depending on the temperature, from a cold start my C will be "on" for 0-10 (maybe 12?) seconds before turning the ICE on (unless I push the EV button and the car complies). In the awful Ohio winter we just had, it'd start within 1-2 seconds. In warm weather, it's up to 10-12. Not sure how this is affected by driving in reverse - it seems that switching from reverse back to drive (then maybe lightly accelerating) encourages the ICE to start, but that may just be a coincidence.

 

Well I guess you are surprised then.

I have a C. Two of them, in fact.
Neither of them uses the battery to any significant degree when the engine is running......ever; at least not that I have seen yet.

This has been discussed here in some detail in a thread I started asking why the "EV mode" button didn't seem to be working.

And while I make my share of mistakes and mis-statements, I do NOT state things as facts that I am not pretty sure of.
There was no "I think" or "maybe" in my previous post.

 

Ok if all you need is validation, and do not wish to be helped, my job here is done.

 

Something is amiss here. What you say isn't practical.

I "start" my C and put it in reverse. By the time it rolls back down the driveway about 20 feet, the engine has started.
I put it in D and start out. After about 20 yards, I am above the 5-10 MPH threshold.......so it has used the battery as the "main source of propulsion" for all of about 10 seconds, maybe less.

For it to really "use the battery as the main source of propulsion" during the whole first minute, you have to stay below 10 MPH. How many people do that ??

Now.....if the engine is not really cold, it WILL use the battery up to about 25 MPH or until it hits the "low charge" point.

I will test further if I remember. I don't honestly remember seeing any battery being used during that first minute.......but might have blinked and missed it during the first few seconds.

 

Not a nice remark. I don't remember asking you for either.
And what you guessed at certainly wasn't helpful to ME.

 

Link to Easy Rider's EV question, for the curious: Max. speed in EV mode, 10 MPH ?? | PriusChat

I guess that depends on your definition of "significant degree", and your normal use. It's entirely possible that if you live/work in the suburbs or a similar area, you've never been met with the conditions required to make significant battery usage during warmup obvious.

• I used to start my drive by backing out of a driveway then driving 1/4 mile down a level 25 mph street, before waiting at a stop sign to turn onto a 35 mph street. I have a light driving foot, so battery usage during warmup wasn't obvious then, since I was past the warmup stage by the time I wade it to the 35 mph street.
• Now I live a reverse and 500 feet from a 35 mph street, so the battery drain is obvious.
• I also sometimes drive 30 seconds from a cold start then go directly onto a 55 mph road with lots of blind spots, so I'm sometimes forced to accelerate more quickly than I (or the C) would prefer. That very quickly drains the battery and forces the ICE out of warmup. I've now learned to listen and feel for the end of the warmup stage before turning onto the 55 mph road, which only takes ~15 seconds extra.

The scenario I'm describing is the first ~1 minute that the ICE turns on after a cold start - the warm-up stage. When the ICE is running in the warm-up stage, it's at a constant, basically idle rpm. The power from it is going to the traction battery. When you're not moving, this results in a net charge to the battery. When you start moving (before the end of the warm-up stage), the ICE doesn't increase rpm to deliver more power - it takes power from the traction battery, which results in a net battery drain unless you're accelerating very slowly.

I think that's how it works in detail, anyway. Keep an eye on the energy flow screen and that might help. If you want to make it more obvious, accelerate harder, or do that when leaving a store or something. If you don't notice it on your daily drive, that's actually a good thing - your drive is what Toyota designed the C for.

Here are two links that describe the warm-up stages in more detail:

• Gen3 warming up stages | PriusChat
  
• http://drivesmartwi.com/uploads/DSW_Toyota_Prius_Initial_Stages_of_Warm-Up_Wayne_Revised_2_.pdf (pdf)

 

Ok here's my 2 cents...

On somewhat of a warm start, my c does this:

Start the car and after a moment, the ICE comes on. Pull out onto the street and accelerate to 45mph. During this acceleration, the ICE remains at the same rpm as it was in the driveway. The acceleration was definitely on the electric motor all the way to 45. It is very smooth and actually adequate. The battery level drops quickly to 2 bars and then the ICE's rpm rises to what would be normal at 45mph. I often wonder what the logic is behind this behavior.

 

The warm-up takes about 5 minutes, and consists of several stages (see link above). It is only during Stage 1 that the battery runs the car. After that, the engine takes over and also begins charging the battery. Gliding is not consistently available until the coolant temp is above 130F or so. I question the use of the battery to accelerate before finishing Stage 1. Your mileage would be better if you waited until the engine takes over and use the battery to extend your glide.