12v battery maintenance, issues, etc.

[TruBlu]

12 hours ago, Max_Headroom said:

This could be the answer - 

 

 

Thanks for the info. This looks like a good idea to keep a check on the Battery state. Problem is: with the Yaris the Battery is in an awkward place and has terminal covers that would interfere with the connecting wires. So I was wondering if the connections could be made to the jump start connector under the fuse box cover (modified to allow wire to go through the cover) and an earth point... would the readings be the same as if connected directly to the Battery?

[Dala]

I use this splitter cable 

https://www.aliexpress.com/item/4000796236558.html

 

1 input - CTEK or OPTIMATE SOLAR 20W
2 input - BM6

[Roy124]

I have the BM6.  My car is in the adjoining garage.  I get good bluetooth about 20 feet away through the  wall. 

I have a CTEK lead hardwired to the Battery and the BM6 connected to that.  I use a long lead from the charger.  Rather than Ali Express, I have ordered 3 Tamiya plugs and sockets and will make my own splitter using the long lead. That will cost about £5.

[Roy124]

Robert, in answer to your question, yes, the fuse box gives the same result.  I only tested by pressing the spade to the positive blade. 

How easy it would be to hard wire it is a different matter.  Hard wiring to the Battery is the better solution.  I got my garage to connect a CTEK lead to the Battery. 

Look at the 12v Battery thread for more discussion. 

[Hibird]

I think in years gone by the vehicle charging system was designed to keep the 12v Battery fully charged as best it could. This improved when the Dynamo was replaced by the Alternator and mpg figures were not the be and end all.

The landscape has now changed and the charging sytem is now designed to also have a minimum impact on fuel economy.

I would imagine the 12v Battery charging strategy has a new level of sophistication to achieve that and may not always result in fully charged batteries. Perhaps a more aggresive charging regime could have acheived a greater charge in less time/miles.

Just my own thoughts and I don't have any real numbers to support them.

On the other hand we have side stepped the trauma of a 'Stop Start' system, thank you Toyota

 

[Roy124]

Mike, I think you are right as any power needed to replenish the 12v can only come from HV regeneration which reduces the HV capacity to power the motor. 

Battery technology has probably changed to limit the full-empty range to a much narrower spread.  No starter motor to hit the Battery for a big charge, no starter motor to drag around when it's done it's start for the day. 

First time I ever gave a thought to batteries was getting a deep cycle one for my caravan. 

[Roy124]

There is a huge amount of data on the web and the link below looks quite good.  It suggests the usable voltage range in 12.7 to 11.7 but recommends recharging at abut 12.7 to 12.5v.  That seems to equate to regular use say every 2-3 days.

I know we hear of people without a problem after a 2 week holiday.  I wonder what the voltages actually were at that point.  

AGM Battery State of Charge – workshoppist.com

[Roy124]

Here is the latest voltage screenshot.  The last journey was yesterday with 2 legs of 1hr20.  Not sure why there is a gap.  The voltage is pretty steady at 12.5v.

[Dala]

1 hour ago, Roy124 said:

Here is the latest voltage screenshot.  The last journey was yesterday with 2 legs of 1hr20.  Not sure why there is a gap.  The voltage is pretty steady at 12.5v.

can you still show the graph with the temperature?
Thanks

for me at the moment:

 

 

[Roy124]

Dala, not tried as the instructions say secure the BM6 to the Battery and I have not tried that.

See what you make of this

[Hibird]

I don't see many new posts about flat 12v batteries so maybe intrest has peaked and the knowledge shared has been absorbed just like the volts.

Even Ken from last week has not returned so is hopefuly sorted.

This thread must have sold a lot of CTEK chargers but my money would be on the Lidl offering.

Of course other makes are available and always have been.

[Max_Headroom]

 

Quote

It depends if it draws current when the car is switched off.

Quote

Try watching the video that is covered

7 hours ago, anchorman said:

"You don’t have to worry about it drawing power too much” doesn’t answer the question 🙄

You are right and that's probably why he gave the information in the video description below  -

Quote

I’ve been having some trouble with my Kia e-Niro’s 12-volt battery and was told about the Quicklynks Battery Monitor II. It’s a Bluetooth 4.0 device that attaches to your 12-volt battery (only drawing 1.5mA) and alerts you of voltage (or problems) when you approach the car.

 Hibrid posted earlier in the thread  that his unit consumes roughly the same and it'll take 450 days to kill a Battery (see below) i don't think it drawing power when the car is switched off is going to be an issue with those who are going to probably monitor the Battery daily.

Quote

That unit consumes an average of less than 2ma so would take around 450 days to drag a fully charged battery down to a 50% charge level if it was the only load.

 

[Roy124]

Made my splitter today so can monitor the charger  as well as the Battery.  The charge sequence is supposed to increase to 14.7v though the BM6 shows it as 15v.

PS now dropped to 14.84v

[Max_Headroom]

Can you post a picture i am sure members would like to see it.

[Derek.w]

Roy124 Gap in your readings I put it down to electronic interferance from another vehicle it most likly wont be repeated for a few days or even weeks.

BM monitors always draw a little curent unless it detect a very low Battery voltage and closes down.

 

 

[Roy124]

42 minutes ago, Max_Headroom said:

Can you post a picture i am sure members would like to see it.

Just a set of plugs.  Two tricks, lay all the male/female parts out for the Y.  Lay out all the plug pins male/female. 

Set out the cables so you get the + / - aligned and you are good to go. 

The other trick was getting the 2 wires of the Y fork into the plug pins. 

I will see if I can get a pic. 

[Roy124]

Monitoring the Yaris Cross Battery for 5 days now I have noted the voltage drop each day between midnight at 10am.  The average loss is between 0.07v and 0.13v.  The average voltage loss is around 0.01v per hour or 1v in 100 hours.  Taking the 0.07v loss that would equate to 1 v in 140 hours.

The start voltage when the Battery is off charge is 12.7v so you could expect the voltage to drop to 11.7v between 4 and 6 days.  This of course is from a very small data sample but suggests that after 14 days in an airport car park you are looking at a voltage of around 10v.

I will continue to monitor voltage drops when my car is unused for longer periods.

From subjective reports many people have not reported any problems.  This suggests that the system starter voltage as low as 10v is sufficient to get in to Ready mode.

From experience with my Corolla when I have experienced a 'flat' Battery the voltage has been around 8v.

I believe voltage excursions below 12v for the AGM battery should be avoided.  My tentative conclusions are:

1.  A fully charged battery will probably have sufficient charge to get the car to Ready mode after 14 days.

2. A solar panel trickle charge will keep the battery with an optimum charge and avoid unwanted excursions below 12v.

3. A jumper pack will be a good investment should the car fail to start at any time.

 

[Hibird]

3 hours ago, Roy124 said:

Monitoring the Yaris Cross battery for 5 days now I have noted the voltage drop each day between midnight at 10am.  The average loss is between 0.07v and 0.13v.  The average voltage loss is around 0.01v per hour or 1v in 100 hours.  Taking the 0.07v loss that would equate to 1 v in 140 hours.

The start voltage when the battery is off charge is 12.7v so you could expect the voltage to drop to 11.7v between 4 and 6 days.  This of course is from a very small data sample but suggests that after 14 days in an airport car park you are looking at a voltage of around 10v.

I will continue to monitor voltage drops when my car is unused for longer periods.

From subjective reports many people have not reported any problems.  This suggests that the system starter voltage as low as 10v is sufficient to get in to Ready mode.

From experience with my Corolla when I have experienced a 'flat' battery the voltage has been around 8v.

I believe voltage excursions below 12v for the AGM battery should be avoided.  My tentative conclusions are:

1.  A fully charged battery will probably have sufficient charge to get the car to Ready mode after 14 days.

2. A solar panel trickle charge will keep the battery with an optimum charge and avoid unwanted excursions below 12v.

3. A jumper pack will be a good investment should the car fail to start at any time.

 

All great stuff Roy at the end of the day it's the numbers that will tell the story.

As you know I have no 12v issues and because of that I have never measured the quiescent current on any of the 2 hybrid vehicles I have owned

I recall a post somewhere here that speculated a quiescent current of up to 50ma may be possible but must stress I have not measured this but based on that number:

0.05 A * 24 hours = 1.2 AH Day

14 days = 16.8 AH

21 Days = 25.2 AH

28 Days = 33.6 AH

I think those calculated figures show that a good 12v Battery should easily cope with a 14 day airport stay and avoid over discharge damage.

However if  any of the following apply it would be a different story.

1) Battery not fully charged when parked

2) Battery is old or damaged

3) Quiescent current is higher than 50 ma

4) Obvious nonsense like interior light ect left on.

I am hoping that stabilized quiescent current readings over a reasonable time period will be your next task for our pleasure and discussion.

Just a note on my take on solar chargers, firstly of course they need sun and the more the better.

If I was buying one for extended airport parking I would be going for a 20w panel as the windcreen will probably turn it into a 10W panel and then it may also be cloudy. However make sure a charge controller is used as the sun may just shine non stop and without a charge controller things may turn very hot ie your battery.

Look forward to your updates Roy

I have just convinced myself to buy a solar panel to negate any risk of battery damage while holidaying in the sun over an extended period of time.

 

 

[Bob66]

16 minutes ago, Hibird said:

Look forward to your updates Roy

I'm not....flipping heck Torchy....gan oot.

[Hibird]

1 hour ago, Bob66 said:

I'm not....flipping heck Torchy....gan oot.

 

1 hour ago, Bob66 said:

I'm not....flipping heck Torchy....gan oot.

Ahh Mr Bumblerop I presume, supplier of fine batteries for Torchy. I had to look him up but it looks like he was a famous TV character in 1959 and even known to the Beatles. You live and learn 😉

[Cyker]

It might not be as bad as that - The initial voltage drop from from 100% for most cell types, including lead acid, is steeper initially, but then levels off after that initial drop 

[Roy124]

1 hour ago, Cyker said:

It might not be as bad as that - The initial voltage drop from from 100% for most cell types, including lead acid, is steeper initially, but then levels off after that initial drop 

Which is why I chose the time midnight to 1000 which gave plenty of settle time.  Equally, why my figures are speculative  as I am yet to 48 hours between starts.  

[Dala]

9 hours ago, Roy124 said:

Monitoring the Yaris Cross battery for 5 days now I have noted the voltage drop each day between midnight at 10am.  The average loss is between 0.07v and 0.13v.  The average voltage loss is around 0.01v per hour or 1v in 100 hours.  Taking the 0.07v loss that would equate to 1 v in 140 hours.

The start voltage when the battery is off charge is 12.7v so you could expect the voltage to drop to 11.7v between 4 and 6 days.  This of course is from a very small data sample but suggests that after 14 days in an airport car park you are looking at a voltage of around 10v.

I will continue to monitor voltage drops when my car is unused for longer periods.

From subjective reports many people have not reported any problems.  This suggests that the system starter voltage as low as 10v is sufficient to get in to Ready mode.

From experience with my Corolla when I have experienced a 'flat' battery the voltage has been around 8v.

I believe voltage excursions below 12v for the AGM battery should be avoided.  My tentative conclusions are:

1.  A fully charged battery will probably have sufficient charge to get the car to Ready mode after 14 days.

2. A solar panel trickle charge will keep the battery with an optimum charge and avoid unwanted excursions below 12v.

3. A jumper pack will be a good investment should the car fail to start at any time.

 

same with me
drop 0.1V/day
 

[Roy124]

18 hours ago, Cyker said:

It might not be as bad as that - The initial voltage drop from from 100% for most cell types, including lead acid, is steeper initially, but then levels off after that initial drop 

Just doing an Eyeball estimate, the voltage drop seems to reduce after about 3.5 hours of switching off. 

[Hibird]

Thought I would share a solar panel update for anyone interested., nothing new here for experts.

I ordered a 20w solar panel which arrived first thing Saturday morning I connected via a charge controller I already have (Victron).

This panel has a maximum output of 1.14 amps which is probably spec'd at midday on the equator. In the UK behind a windsrceen I would guess around 400ma max and probably less even on a sunny day. I may measure it one day.

I had one of these panels before but gave it away for someone to illuminate a pond at night and they seem happy with it (fish may not be so keen) but it still works and lives happily outside 24/7.

Stabilised Battery voltage prior to connection was 12.65v (car had been used for around 30 mins) voltage Sunday morning was 12.41v and this morning 12.42v (prior to sun hitting panel) so a grand total of 48 hrs very early days.. Where the car is parked it is only getting around 3 hours of weak spring sunshine with partial cloud. I guess if I moved the car to maximise solar exposure things would improve leaps and bounds.

Battery voltage is now 12.58 V after 1 hour of todays direct sunshine and will probably rise to 12.8v after 3 hours of direct sun.  

I will update here if there is any interest but would suggest this would extend safe airport parking time by a significant margin and longer than I would want to pay for and maybe even for ever.😉

Of course daylight hours and sun cloud ratio throughout the year are not a fixed quantity so would not suggest it is a total solution for everyone but what is !

However this could be a helpful bit of kit for those where other solutions are not possible or working and could make a huge difference to those suffering most.

My key bit of advice would be don’t be tempted to go for a low output solar panel.