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AT21

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Hi all Newbie here, I have just completed a 100 mile non stop journey so the battery should be fully charged.
Just switched the engine off my LR EV and got the following message on the dash, I have had it for several months and never had it before.
1663844357166.jpeg

Any ideas, I have tried disconnecting the battery for 10 minutes
 

JCFlippen

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Could be a hint that the battery is on its way out - not an unknown issue. Can you charge it up on your own charger if you have one and see if it retains charge?
 

AT21

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Could be a hint that the battery is on its way out - not an unknown issue. Can you charge it up on your own charger if you have one and see if it retains charge?
I have charged it, and overnight it went from 13.1 to 12.5, don’t know if that’s ok
 

Jomarkh

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If the voltage dropped after being on charge then is sounds like a battery issue.
Book it in with your garage.
 

hmadsen

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That would be a warranty issue.

More than a few have had problems with the 12V battery.

Some have just opted to replace it with a quality battery at their own expense
 

N2STY

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I do fear this could be because of the high battery charging rate it boils the battery acid and when there is not enough acid to cover the cells 12v batterys go down hill very quickly
 

Bodgerx

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I do fear this could be because of the high battery charging rate it boils the battery acid and when there is not enough acid to cover the cells 12v batterys go down hill very quickly
Why would the 12v battery charging rate be 'high'?...that's controlled by the DC-DC convertor, so unless that's failed in someway it's unlikely to be over charging it...
 

N2STY

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For a 12v lead acid this is typically 14.4v (fast) and 13.8v (standard) and maybe 13.1v (maintainance.)
Sitting at fast all the time is not healthy mine sits a 13.8v when driving but some people are seeing 14.1v but when my car is plugged in its sits at 14.6 a bit over kill for a standard 12v battery properly OK for a AGM battery
 

N2STY

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Why would the 12v battery charging rate be 'high'?...that's controlled by the DC-DC convertor, so unless that's failed in someway it's unlikely to be over charging it...
One possible reason is software is set up for AGM but they then used a standard battery as the price difference would be a big saving then to cover them self's only give a one year warranty on battery when batterys have had 4 years warrantys for a long time now
 
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MichaelJHunt

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A 12V battery is fully charged at 12.6V.

When being charged, the charging voltage must be higher than the battery voltage to allow current to flow to the battery and charge it.

The rate of charge is determined by the current delivered by the device charging the battery, not by the voltage difference.

When you quiz the car and it indicates a battery voltage level greater than 12.6V this is because as a side effect of quizzing the car using the app it also brings in the DC-DC converter and charges the battery, shoving up to 50Amps into it depending on its state of charge.

To measure your battery voltage level correctly to need to put a voltage meter across the battery terminals when the car is completely powered down.

12.6V = fully charged
12.4V = 75%
12.2V = 50%
12.0V = 25%

With an ICE, 12V probably means you would not be able to start the car.

With a BEV 12V probably means you can't bring in the HV battery contactors and the car is then "bricked".

When the car is fully powered up and in the READY state the voltage measured across the battery terminals will be much higher than the 12.6V, typically anything from 13.0V to 14.5V.

It should be noted that it is understood that the BMS also looks after the 12V Battery Level when the car is powered off and the doors are locked. This is NOT true if you are using the V2L feature with the car powered off and the doors locked.
 
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Lovemyev

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For a 12v lead acid this is typically 14.4v (fast) and 13.8v (standard) and maybe 13.1v (maintainance.)
Sitting at fast all the time is not healthy mine sits a 13.8v when driving but some people are seeing 14.1v but when my car is plugged in its sits at 14.6 a bit over kill for a standard 12v battery properly OK for a AGM battery
Here is what I see on our Gen 2 LR Trophy.
Some figures are taken from the App health check report.
12 volt battery status when at rest ( car powered down and parked ) around 13.1 volts, according to the App.

68B313E5-DE4B-46AC-8815-56E2DC68D538.jpeg


When the car is in motion, a constant 14.1 volts is seen in the dash panel read out.

AAF89A78-FA11-49BA-9DDF-C85FC3A46AFA.jpeg


When the car is on charger 🔌 ( like now ) the voltage reported by the App is high at 14.8 volts.

F35298EF-30AA-42E0-8781-181D47ECFAC5.jpeg


This would suggest that the 12 volt battery is receiving its highest charge rate, when the car is receiving a charge from the A/C supply.
Namely our 7Kw 32 Anp single phase wall box in the U.K.
 
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N2STY

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That does sound a bit high for normal 12v battery and more in AGM territory so mine is 13.1 rest 13.8 drive 14.6 ac charge
 
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