Clubjazz - Honda Jazz & HR-V Forums

Honda Jazz Forums => Honda Jazz Mk4 2020 - => Topic started by: Ioannis on February 05, 2022, 12:28:24 PM

Title: Battery never below 3 or above 7 notches?
Post by: Ioannis on February 05, 2022, 12:28:24 PM
Our new white Jazz Executive was delivered a couple of days ago - I drove it in the city, countryside and motorway and the battery indicator fluctuates between 3 and 7 notches, but never shows 10 notches, e.g. full. I love the little car and how it drives, but is there any way to get the battery to show "full", e.g. 10 notches? Or is this not relevant for Lithium batteries?
Title: Re: Battery never below 3 or above 7 notches?
Post by: Kremmen on February 05, 2022, 12:33:34 PM
Mine will often show 10 bars after a weeks storage or after a trickle charge.

Once out on the road though it's back to 3 to 7
Title: Re: Battery never below 3 or above 7 notches?
Post by: ColinS on February 05, 2022, 01:10:39 PM
John posted this in another thread a short while ago:
One factor is how easy is it to remove / replace the battery pack and whether the vehicle and battery have been designed with consideration to long term repair. The battery pack in the Mk 4 Jazz is relatively small and probably accessible without too much difficult. Another factor is how the battery is managed, bearing in mind that the more it is operated towards the ends of the charge range then the faster the lithium chemistry gets worn out. It's clear that Honda have considered this aspect as the charge level spends most of its time between 30% and 70%. Less than 30% is only used for short periods when power is needed and the battery already down to 30% while charging above 70% only happens when going down a long hill. The design of the Mercedes mentioned in the first post may use the full battery capacity. If it's a PHEV and the battery is left with a low charge for some time then the chemistry suffers badly.

I believe that the battery in the hybrid Mk 2 Jazz is nickel-metal hydride which is more tolerant to being used over the full charge range but has lower charge density than lithium batteries. See also https://www.honda.co.uk/engineroom/electric/ultimate-hybrid-car-faq/ .
Title: Re: Battery never below 3 or above 7 notches?
Post by: Derkie54 on February 05, 2022, 01:50:06 PM
When I go down a long hill mine regularly shows all 10 bars.
Title: Re: Battery never below 3 or above 7 notches?
Post by: guest9814 on February 05, 2022, 03:47:51 PM
When I go down a long hill mine regularly shows all 10 bars.

But  never getting 100% charge - maximum that I seen through OBD monitoring app Car Scanner on long downhill is 95% and then ice  engine braking comes up.
Title: Re: Battery never below 3 or above 7 notches?
Post by: Jazzik on February 05, 2022, 06:46:08 PM
I see 10 bars regularly, without driving down a long hill or plugging in the trickle charger.
At low temperatures (around + 2 °C or lower) starting with cold engine, heating at 21 or 22 °C. The ICE continues to work to bring the interior to the required temperature, but in the meantime also charges the battery, often up to 10 bars...
Title: Re: Battery never below 3 or above 7 notches?
Post by: Kremmen on February 06, 2022, 05:20:55 AM
I'm convinced my infrequent 10 bars display is a wrong reading. Something is getting confused, but out on the road it corrects itself.
Title: Re: Battery never below 3 or above 7 notches?
Post by: Jayt43 on February 06, 2022, 06:30:31 AM
I see 10 bars regularly, without driving down a long hill or plugging in the trickle charger.
At low temperatures (around + 2 °C or lower) starting with cold engine, heating at 21 or 22 °C. The ICE continues to work to bring the interior to the required temperature, but in the meantime also charges the battery, often up to 10 bars...

Yes, same here. Poland and Hungary have colder winters than UK, so the Jazz's battery benefits in the morning :-)
Title: Re: Battery never below 3 or above 7 notches?
Post by: Lord Voltermore on February 06, 2022, 06:59:22 AM
I think to reassure the OP   ,in normal driving on level roads the battery doesnt normally go above 7 .  By 7 it  will  be using the battery for electric drive. The Battery prefers not to go above 70% charge too often.

    But it can go up to 10 on long downhill stretches (even slightly down hill)  where the car is generating  more electricty than its using  to drive the electric motor.  When the battery gets near 100% any further charging is used for braking or it stops charging.

You may not have experienced this yet.

    Like Kremmen I have seen it go above 7 when the car has been parked for a few days.  I dont know why this happens.  Possibly just the voltage giving a slightly false reading at rest. It does seem to drop from 10 quite quickly.
Title: Re: Battery never below 3 or above 7 notches?
Post by: peteo48 on February 06, 2022, 10:59:50 AM
I do get 10 bars from time to time although 3 to 7 is the most common range. What happens with me is the battery will go up to 10 bars on a cold day and on a short trip. My theory is that the engine is on almost constantly to generate heat for the cabin and, at the same time it's charging the battery.
Title: Re: Battery never below 3 or above 7 notches?
Post by: PaultheManc on April 30, 2022, 11:04:14 AM
Just a few days with my new Jazz Hybrid and pondered this question as I was driving.  The excellent Honda Tech video explaining how the Honda hybrid system works gives some insight into this.  The battery is there to optimise the efficiency of the hybrid engine.  I believe it will normally aim to be about half charged - this way it can provide power when advantageous or store power (e.g. when the ICE is heating the car) when it would otherwise be wasted.  You should expect to do a lot of EV driving if the battery gets to 100%, so that the battery state aims to reach the normal mid range level.  Just my tuppence.
Title: Re: Battery never below 3 or above 7 notches?
Post by: shufty on April 30, 2022, 12:10:54 PM
... I've never seen mine go below 3 but does reach 10 sometimes, as mentioned it doesn't require a long downhill section to achieve this.
Title: Re: Battery never below 3 or above 7 notches?
Post by: John Ratsey on April 30, 2022, 05:18:34 PM
... I've never seen mine go below 3 but does reach 10 sometimes, as mentioned it doesn't require a long downhill section to achieve this.
I've seen my gauge occasional drop to 2 bars if a power boost is needed (eg for overtaking) when the battery is already down to 3 bars so the battery provides a brief surge of power while the engine is building up speed.
Title: Re: Battery never below 3 or above 7 notches?
Post by: nowster on April 30, 2022, 06:14:59 PM
In highway/motorway cruise driving, I see it cycle:

- Engine drives wheels (either directly or indirectly via generator) and also charges battery up to 7 bars
- Battery only mode until it drops to 4 bars
- repeat
Title: Re: Battery never below 3 or above 7 notches?
Post by: shufty on May 06, 2022, 04:15:02 PM
... I've never seen mine go below 3 but does reach 10 sometimes, as mentioned it doesn't require a long downhill section to achieve this.

... Actually saw 2 bars today.
Title: Re: Battery never below 3 or above 7 notches?
Post by: Marmoset on May 07, 2022, 06:18:36 PM
When I go down a long hill mine regularly shows all 10 bars.
It's the same for me too.  Driving in B mode seems to push the level up more as well.
Title: Re: Battery never below 3 or above 7 notches?
Post by: Kremmen on May 17, 2022, 08:07:13 AM
I can't fathom the logic between engine on / off and the battery bars.

You would expect the bars to drop to 3, then the engine fires up, then when they get to say 7 the engine cuts out and you're on EV.

I use the instant MPG bar as a good indicator as the engine on / off. The engine seems to power up randomly, even when I'm showing 3 to 7 bars.

It all works OK so I'm not at all bothered.
Title: Re: Battery never below 3 or above 7 notches?
Post by: Lord Voltermore on May 17, 2022, 09:40:56 AM
I can't fathom the logic between engine on / off and the battery bars.

You would expect the bars to drop to 3, then the engine fires up, then when they get to say 7 the engine cuts out and you're on EV.

I use the instant MPG bar as a good indicator as the engine on / off. The engine seems to power up randomly, even when I'm showing 3 to 7 bars.

It all works OK so I'm not at all bothered.
Same here.    Sometimes ,even with plenty  of battery bars and a slight downhill slope  , "computer says No" to using EV mode . Or may say "Yes" in apparently less favourable circumstances .  As long as I get good mpg results  , and someone in Honda knows the answer and research continues into perfecting the system , I am content to remain in ignorant bliss.   Plenty of other  things to worry about.  ???

I'm getting particularly good mpg at present  (75mpg)   Possibly in the weather sweet spot of rapid warm up  with little need to use energy  for heating or air conditioning.   :-*
Title: Re: Battery never below 3 or above 7 notches?
Post by: PWV on June 03, 2022, 07:38:36 PM
Good answers LV & PtM...picked my Jazz yesterday and was rather disappointed that it didn't get above about six bars.  But of course I realised that it would start using ev mode more and for longer.  So no need to get in touch with dealer except living in a flat area I might have difficulty leaving the battery fully charged when I go on Holliday.

I don't think starting the power and being stationary will charge the battery.
Title: Re: Battery never below 3 or above 7 notches?
Post by: Kremmen on June 04, 2022, 05:32:24 AM
Yes it does.

I've got a voltmeter plugged in and when the power is started, whether the engine fires up or not, it jumps from 12v to 14.5v, exactly the same as starting an ICE car.
Title: Re: Battery never below 3 or above 7 notches?
Post by: sportse on June 04, 2022, 06:16:11 AM
My HV battery bar didn’t used to move when powered up and not driving.

After a full 12V battery disconnect for an hour, it now acts like other hybrids I’ve had.

The battery gauge goes up when the petrol engine is on, then goes down when it’s off and the cycle repeats while parked in ready mode.
Title: Re: Battery never below 3 or above 7 notches?
Post by: Botak on June 04, 2022, 09:40:29 AM
So no need to get in touch with dealer except living in a flat area I might have difficulty leaving the battery fully charged when I go on Holliday.

I don't think starting the power and being stationary will charge the battery.

There is I think no need to have the lithium battery fully charged while on holliday. When we were away for more then three months the car was parked with the (lithium)battery at 5 bars. When we came back the battery was still at 5 bars. The lithiumbattery discharges very very slowly. Its of course different for the 12 voltbattery.
Title: Re: Battery never below 3 or above 7 notches?
Post by: guest9814 on July 09, 2022, 03:08:31 PM
Interesting
I observed that many times, when i most of week doing 25-30mph drive (during this drive battery charges maximum to 43 % then at holiday i drive to supermarket on flat road  with speed 37mph for long enough the hybrid system charging battery using ICE  to virtually 100% - 10 bars, maybe for balancing cells or some sort of calibration.
Title: Re: Battery never below 3 or above 7 notches?
Post by: sportse on July 09, 2022, 04:18:31 PM
I managed to max out my battery today, it was weird as the car was in EV but revved when you braked.

It sounded ok, the Prius engine brake is more noisy.
Title: Re: Battery never below 3 or above 7 notches?
Post by: guest9814 on July 17, 2022, 06:41:28 AM
Interesting
I observed that many times, when i most of week doing 25-30mph drive (during this drive battery charges maximum to 43 % then at holiday i drive to supermarket on flat road  with speed 37mph for long enough the hybrid system charging battery using ICE  to virtually 100% - 10 bars, maybe for balancing cells or some sort of calibration.
Correction this happens one time after  car powered on. And only up to 9 segments, this around 90%.