12V battery after long stand-still

[Botak]

We are happy pensionnars (that's why a Jazz?) and we stay in winter a couple of months in the sun in Spain. The battery of our previous car (Toyota corolla verso) had no problem with that. But I was afraid that with a Jazz hybrid and a small 12v battery it could be a different story. So I was very curious how it would go. Here is a report for anyone interested.
The Jazz is parked in a garage, where unfortunately there is no electricity. So no possibility for a trickel charger.
On departure, the battery condition was measured with a multi-meter: 12.8V. (and the traction battery had 5 blocks). Furthermore, no special measures have been taken, so the keyless system has remained active (I assume).
When we returned after two and a half months, I checked the battery without starting the system (I had left the engine compartment unlocked). The meter read 11.9V. I have not tried to start the system on the battery, but I first connected a starting aid (this starting aid: https://www.lidl.nl/p/ultimate-speed-mobiele-autostarthulp-met-powerbank/p100337742 ) and then started the car. That went fine. After releasing the starting aid I made a trip of more than an hour.
The next day I measured the voltage of the battery again and it was 12.6V.
My conclusion is that the small battery can hold a lot more than I expected and that it can last for a while. But after a year or two I'll replace the battery with an EFB one (assuming it's available for the Jazz). They are more resistant to deep discharge I understand, so that, even after a very cold winter and deep discharge, I don't have to worry about the condition of the battery after a very long standstill.

[Kremmen]

Useful info thanks.

Fortunately the 12v battery is not required for starting/powering up so dropping below 12v is not as critical.

[Jazzik]

The car would have started (without the jump starter) without any problems...

[sportse]

Many thanks, it’s good to see that the Jazz batteries will keep a charge for a long time.

Should the battery need replaced at some point in the future they aren’t too expensive being plain  batteries.

FYI on the service schedule for mine there is a space on the checklist for the battery to be put through a midtronics battery tester and the code recorded.

It was good to see this when I had my car serviced, lots of dealers for other manufacturers don’t do this.

(My previous Toyota hybrids were bad for keeping a charge, I had to carry a portable jump starter in the car in case I got stuck. The Toyota hybrid batteries are expensive ones too. )

[Jazzist]

A new 12 Volt battery was placed in my Jazz this week. 2 times I had to call roadside assistance because the car did not open and did not start. According to the garage, the cause was that the GPS remained on in the navigation system. An update has been performed. When I got home after the garage visit I measured the voltage. It read 12.88 V. Today, 3 days later, it shows a value of 12.27 V exactly after 72 hours. Didn't drive the car, only opened the door to open the hood. Is this a normal loss of power at standstill?

[Kremmen]

I don't know whether this still applies......

When I had my first 8G Civic I was told by a Honda employee to always double lock the car. He said the single lock does leave some systems running but the double lock shuts down everything not needed.

As a result I touch the door handle 'hamburger' to lock then within a few seconds touch it again and it does make a familiar double lock sound.

[Lord Voltermore]

I just got back after 7 weeks away,  23 january to 14 march.    The car was outside, unattended.   During this time I had a solar charging panel plugged into the obd ll  port .           The car started.

I used the following   .   
https://www.ebay.co.uk/itm/124650941856

Its only about 2.4 watt giving 0.13 to  0.2 amps  trickle charge in good sun.   But even with short winter days its charging light was flashing, and appears to have done the job , although the car might have been ok anyway.


The panel is quite large  ,about 350mm x 210 mm.      The only problem I found is the obd ll port on the jazz is a bit tucked away, and is mounted on quite a flimsy bracket that moves a bit when I try to plug the connector in . The connector is quite a tight fit, so I was a bit uncertain whether it had been fully inserted.  The  panels charging light flashes anyway whether its plugged in or not.       It may be easier and more certain just to connect it direct to the battery  using the supplied battery clips. In which case  there are cheaper alternatives without  an obd ll connector.   

It wouldnt be suitable for a car left in a garage, unless there is a good window. 
 

[John Ratsey]

When I got home after the garage visit I measured the voltage. It read 12.88 V. Today, 3 days later, it shows a value of 12.27 V exactly after 72 hours. Didn't drive the car, only opened the door to open the hood. Is this a normal loss of power at standstill?

I think some drop in voltage within a few hours of charging being stopped is normal.

My Crosstar frequently spends a couple of weeks between uses and the battery is usually down to 11.8V but that's sufficient to start the car. More accurately, it's sufficient to power up the 12V system including the ECU and once the vehicle is alive then the HV battery (which, being Lithium, holds its charge very well) can come into use. I've also found that if I connect an intelligent charger when the battery is down to 11.8V then it only takes about a minute for the charger to say that the battery is fully charged which suggests that while the voltage is down, there's plenty of capacity remaining.

I also recall that the handbook says that the vehicle should be used for at least 1/2 hour every three months to keep the battery healthy.

[Botak]

I just got back after 7 weeks away,  23 january to 14 march.    The car was outside, unattended.   During this time I had a solar charging panel plugged into the obd ll  port .           The car started
 

I would have used it if I knew. Our garage does not have a window but I would have fixed it on the roof (stormproof!). But as it is now I trust that the battery will stand out 3 years of winter-standstills. Every 3 years a new battery would be OK with me. And at the first batterychange I will opt for an EFB (like this one: https://www.accuserviceholland.nl/dynac-auto-accu-efb-start-stop-12-volt-40-ah.html. The specifications seem OK)

I also recall that the handbook says that the vehicle should be used for at least 1/2 hour every three months to keep the battery healthy.

Does not that apply at the HV-battery? Then 3 month is very "safe".I suppose that the battery-charge of the HV battery could last very much longer. They keep charge very well. At departure the charge was 5 blocks, at return after two and a half month it was still 5 blocks.

[Jazzist]

I just got back after 7 weeks away,  23 january to 14 march.    The car was outside, unattended.   During this time I had a solar charging panel plugged into the obd ll  port .           The car started.

Thanks for your information. I wonder if the OBD plug can be kept plugged in all the time or does it have to be removed after the engine has started

[Jazzik]

How often does the problem of not starting due to an empty, (too) small 12 volt battery actually occur among owners of a hybrid?
We have been driving a small hybrid for almost 5 years now. More than 4 years a Yaris Hybrid (original battery) and now a Jazz e:HEV for half a year. Both according to insiders with such a (too) small 12 V battery.
Never encountered this problem to date. It was and is (fingers crossed) getting into the car, safety belt, pressing the brake and starting.
Never measured voltage, never used a charger (which is gathering dust in the garage), never even thought of a 12V solar energy panel trickle charger... Both the Yaris and the Jazz always started without any problem, also after a few weeks of "rest".

[sportse]

It was fairly common on the Auris/Yaris hybrid groups I was a member of when I had mine.

Short trips or parking for a week or two between journeys all destroyed the expensive 12V batteries in these. Once run down they were damaged and wouldn't fully charge ever again.

People were taking their cars back to the dealer to complain and being told they need to connect it up to a trickle charger if they are only doing short journeys.

It's also more likely to occur if you park outside rather than in a garage, as that avoids some of the temperature issues.

[culzean]

Batteries are often the most neglected and least understood part of a car... which means trouble ahead when the only way a car can move is using a battery.  I have no doubt people will think it is a great idea to keep the Li-Ion battery on their care absolutely 100% charged all the time, when in reality that will kill the battery pretty quick.

[Kremmen]

Yep, my Smartphone has an option to limit charge to 85% to prolong battery life.

[Lord Voltermore]

I just got back after 7 weeks away,  23 january to 14 march.    The car was outside, unattended.   During this time I had a solar charging panel plugged into the obd ll  port .           The car started.

Thanks for your information. I wonder if the OBD plug can be kept plugged in all the time or does it have to be removed after the engine has started

Instructions say you must unplug the panel before starting the car.  In theory you could leave the obd ll lead connected and just unplug  it from the solar panel,  but its big. (approx 40mm x 100mm.)   On a Right hand drive car it would obstruct the driver  , and even if this were the passenger side on a left hand drive car  they could easily kick it and possibly damage the obd ll port.   Using the OBD ll port is probably only  suitable for occasional long absences.