Hv Battery Charge Level

[Holgervaga]

Hi everybody.

I have been truly satisfied with the recent purchase of Auris Hybrid.

Curious about one thing.

I have seen the Battery levels reaching 6 bars quite rapidly, but never beyond.

Just to prove the point I have occasionally tried to drive in the manner that should allow the charge to reach max, but 6 bars have remained my ceiling.

Now my question: is it just me?

Thank you!

[Grumpy Cabbie]

It's perfectly normal for the car to sit at 6/8 bars. You will go to 7/8 and even 8/8 bars when you go down a long hill. If you ever do go down such a long, steep hill, you'll probably find the car revs away at about 3 or 4k revs. This too is normal. Such long hills are where you really should use the B mode on your gear selector.

The car will also not go below 2/8 bars unless you foolishly leave it in Neutral with the a/c on for extended periods, as the engine will automatically fire up to top the car up again to protect it. Leaving it in Neutral stops the car doing this. Also, if people run out of petrol and continue to drive the car on the Battery, it will run the Battery too low and 'can' damage it.

The short reason why the car normally sits at 6/8 is to allow room for regen when going down hills (or similar). Also, the reason why the Toyota hybrid Battery lasts for the life of the car (well over 100k miles) compared to a similar tech mobile phone battery, is that the car only utilises about 40% of the total capacity available to it, compared to 100% on a phone. This small 40% window (roughtly between 40% and 80%) is why the battery lasts. So even when the car says it's totally and utterly full, 8/8 bars, it's actually only about 82% full.

Have a read of this link;

http://en.wikipedia.org/wiki/Toyota_Prius#Batteries

The car will try to sit at 6/8 bars, or roughly 60%.

There was a chart on the US Prius forum that showed the number of cycles the HV battery is capable of. If it were used 0-100% like in a mobile phone, it would only last about 1,500 cycles before dying and needing expensive replacement. But as the window is tightened the number of cycles increases to the point of about 150,000 full cycles in the window presently used.

There's a lot, lot more to it than this, but hopefully this gives you an idea of what's going on.

[Holgervaga]

Your reply explains a lot.

Thank you!

[johalareewi]

The car will also not go below 2/8 bars unless you foolishly leave it in Neutral with the a/c on for extended periods, as the engine will automatically fire up to top the car up again to protect it.

Leaving it in Neutral stops the car doing this.

Although one Auris owner (terry953), discovered the HSD will suss this and can top the HV Battery up to stop it going below 2 bars while in N. There is a post somewhere on this forum but the wonderful search facility can't find it.

Also, if people run out of petrol and continue to drive the car on the battery, it will run the battery too low and 'can' damage it.

This is very important.

On the Gen3 Prius and similar (like hybrid Auris), if the fuel runs out, the car will run on HV Battery BUT WILL NOT TELL YOU. Then the HV Battery runs out and the car becomes a brick. You will have to be rescued by Mr T and the car will have to reset by a Toyota dealer. You can't just put some more fuel in and start it up again.

[Grumpy Cabbie]

Well it tells you by having a fuel gauge, a distance to empty gauge, a beep at about 30 miles remaining (and possibly at 0).

Ignore all those warnings at your peril.

Most times Mr T can charge up the HV Battery, pop some petrol in and away you go. Some times the HV Battery becomes a very expensive paper weight and isn't covered by your warranty.

[timberwolf]

The car will also not go below 2/8 bars unless you foolishly leave it in Neutral with the a/c on for extended periods, as the engine will automatically fire up to top the car up again to protect it.

Leaving it in Neutral stops the car doing this.

Although one Auris owner (terry953), discovered the HSD will suss this and can top the HV Battery up to stop it going below 2 bars while in N. There is a post somewhere on this forum but the wonderful search facility can't find it.

The HSD design can not charge when it in Neutral because the two electric motors and petrol engine are permanently coupled by the Power Split Device and instead an open-circuit in the Motor Generator coils is employed to achieve Neutral.

If the car was capable of overriding N, that would mean the computers had been designed to switch into either D, B, R or P, that seems unlikely and a dangerous choice.

[Grumpy Cabbie]

I wonder if the car will just stay at 2/8 bars for a long time giving the impression it's not dropping, when really it's probably gone from 40%, 30%, 20%, 15%?

A scan gauge seems the popular choice in the US to gain such information.

[timberwolf]

I think we can assume that the scale is not linear e.g. see the bottom of the page for SOC % http://privatenrg.com/indexOldSite.html

[Grumpy Cabbie]

And I suppose we'd better tell him the levels can change depending on temperature. Park it at 6/8 one evening and wake up the next morning at 7/8 or 5/8. Or vice versa. But I was trying to keep it simple. I notice he's not been back in

[Holgervaga]

I am still keeping an eye on the conversation, but the first answer satisfied my curiosity well enough :)

Thank you!

[PeteB]

[1] ...Most times Mr T can charge up the HV battery...

[2] ...Sometimes the HV battery becomes a very expensive paper weight and isn't covered by your warranty...

[1] do we know if Toyota have more chargers now?

I know of two occasions (not recently) where a driver filled up with diesel [2] and after many attempts to start the car by the owner, fleet manager (in one case), RAC/AA and dealer the HV Battery was flattened enough to preclude starting the car - first occasion was more than 10 years ago with a Gen 1, other occasion around 7 or 8 years ago in a Gen 2.

Both times the problem was made worse because there was only one charger in the whole of Europe, and it wasn't in the UK!

Each time they dealer had to go into a booking queue, and it took some weeks before the charger arrived at the appropriate dealer. I can't remember if the Gen 1 HV Battery survived, but by the time the Gen 2's Battery was recharged to was too late to save it.

[MEP's Yaris GS]

I suppose this is one advantage of a PiP - built in HV changer haha.

[Grumpy Cabbie]

I suppose this is one advantage of a PiP - built in HV changer haha.

Dare to try running a PIP totally flat then - including the hybrid side?

[MEP's Yaris GS]

I suppose this is one advantage of a PiP - built in HV changer haha.

Dare to try running a PIP totally flat then - including the hybrid side?

I'll pass, if a normal Prius HV unit is £1200 new fitted I hate to think what it is for a PiP if it does go Pete tong.

[barrycoll]

Talking of charging batteries, with my wife in Oz for 3 weeks, the Prius is left high and dry......to be on the safe side I have connected it up to the CTek charger in the driveway, slammed the bonnet, and left it showing green for charged and maintaining...

Will any of this trickle charge find its way back into the HV Battery I wonder???

Anybody know of anything else one should do when not using the car for long periods??????????

[MEP's Yaris GS]

I doubt it'll trickle back to the HV as the systems are not connect when switched off to the best of my knowledge. But whats with the bonnet slamming, the 12v is in the boot isn't it?

[Grumpy Cabbie]

I doubt it'll trickle back to the HV as the systems are not connect when switched off to the best of my knowledge. But whats with the bonnet slamming, the 12v is in the boot isn't it?

It is, hidden away under the floor (sort of). It's a tiny Battery squeezed into a little cubby hole.

The correct jump start terminals are in the front next to the engine. I would imagine that would be a good place to attach a charger but having left my car for 3 weeks and not had a problem (so far), I personally haven't bothered. I now do 3,000 miles a year if that.

[barrycoll]

Yes, Jono, I use the dedicated red terminal on the right of the engine bay....the Ctek fits in neatly and gives a nice confidant feeling.... the Ctek does come with a lead than can be permanently fixed to the Battery terminals, leaving just a fool proof connector...this doesn't work with the dedicated under bonnet terminals though

I suppose that my 5000 miles G.C. is made up of a 3k miles to Spain in June, and the rest around the UK or Europe....our IQ does the local donkey work, and as London suburban streets are so narrow with parked cars, the IQ is a relief after the relative width of the Prius

[MEP's Yaris GS]

I'll have to hunt for said terminals under the bonnet, never noticed them myself previously. Where exactly should I be looking out of interest?

[Joseph D]

... Where exactly should I be looking out of interest?

The attached image shows the location, standing at the RHS of the engine bay looking across to the LHS with the fuse/relay box cover removed.

The image shows the terminal with the safety cover raised. The actual charging tab is to the left of the circled nut in this image. When standing in front of the fuse/relay box, as you would to attach your charger, the connection tab would be behind the circled nut.

Prius Fuse/relay box with exposed jumpstart terminal.

Two words of caution when jumpstarting the Prius:

• DO NOT connect the jumper leads with incorrect polarity.
• DO NOT have the donor car running.

Doing either of these can cause £1,000+ of damage to the inverter in seconds.

HTH.

[barrycoll]

the Ctek device prevents wrong polarity...or at least it wont work if you connect neg and pos wrongly

here are some pics of my set up

[MEP's Yaris GS]

Thanks for the pic's Barry, should I ever need to jump my PiP at least I know where to do it now :)