CTEK charger advice please.

[badlywornroy]

2 hours ago, CassUK said:

A fully charged 12v battery should be 12.7v

As a guide the below figures are near enough for a decent understanding and reference as to how your battery stands:

 

Lead Acid

12.7v - fully charged

12.5 - 90%

12.4v -75% 

12.2v - 50%

12.0v - 25%

11.9v/below - fully discharged

Many thanks Neil,  that is a great help  to me. 😀

[JasonM]

Yes agreed and those values make sense for a non hybrid car with a starter motor and high cranking current but the Toyota hybrid only needs 12v for starting so any voltage above 12v is a bonus. 

[badlywornroy]

1 hour ago, JasonM said:

Yes agreed and those values make sense for a non hybrid car with a starter motor and high cranking current but the Toyota hybrid only needs 12v for starting so any voltage above 12v is a bonus. 

Thank you for confirming that Jason. 🤗

[Red_Corolla]

2 hours ago, JasonM said:

Yes agreed and those values make sense for a non hybrid car with a starter motor and high cranking current but the Toyota hybrid only needs 12v for starting so any voltage above 12v is a bonus. 

The Battery needs to be maintained in a well-charged state for it's own benefit, does it not? I'm thinking about sulphation and the effect that can have on the overall lifespan, assuming that's still a concern with modern batteries?

[CassUK]

2 hours ago, JasonM said:

Yes agreed and those values make sense for a non hybrid car with a starter motor and high cranking current but the Toyota hybrid only needs 12v for starting so any voltage above 12v is a bonus. 

Any 12v auxiliary circuit Battery will degrade over time and it will be flat at 11.9v.
 

I don’t know what voltage the generator in the C-HR hybrid puts out but given the number of reported auxiliary Battery failures, the Battery either doesn't get enough charge, or the car isn’t used enough or the battery capacity isn't big enough (I’ve read that the Mk II C-HR has a larger capacity battery).

I’d be interested to know the actual charging rate is to the auxiliary battery and the typical battery voltage when the car has been parked up and left for more than 2 hrs. You also need to factor in any parasitic drain from electronic systems such as alarms etc when parked.

[Derek.w]

7 hours ago, CassUK said:

A fully charged 12v battery should be 12.7v

As a guide the below figures are near enough for a decent understanding and reference as to how your battery stands:

 

Lead Acid

12.7v - fully charged

12.5 - 90%

12.4v -75% 

12.2v - 50%

12.0v - 25%

11.9v/below - fully discharged

Type of car makes no diffrence to the Battery state of charge but Battery type will or waking up electronics to take a reading ie opening a door.

[JasonM]

On 10/15/2024 at 9:29 PM, CassUK said:

Any 12v auxiliary circuit battery will degrade over time and it will be flat at 11.9v.
 

I don’t know what voltage the generator in the C-HR hybrid puts out but given the number of reported auxiliary battery failures, the battery either doesn't get enough charge, or the car isn’t used enough or the battery capacity isn't big enough (I’ve read that the Mk II C-HR has a larger capacity battery).

I’d be interested to know the actual charging rate is to the auxiliary battery and the typical battery voltage when the car has been parked up and left for more than 2 hrs. You also need to factor in any parasitic drain from electronic systems such as alarms etc when parked.

Hi,  When I am driving the charging voltage I have seen is only 12.8V, this goes up to around 14.5V when the car is in Park.  12.8V is hardly enough to maintain the charge in the Battery, but I haven’t monitored over a long time yet so not sure of charge voltage goes up when Aux Battery charge drops very low.   Normally my Battery sits at 12.2-12.3V when stationary.

[badlywornroy]

So bearing in mind the above is there an arbitrary Battery voltage when you consider it's time to stick the car in 'ready' mode or put it on charge. Or maybe it's not that simple ?

[JasonM]

I tend to put the car in park and charge for 30-45 min once every 2-3 weeks anyway. If the voltage drops to around 12.2V or below I generally give it a boost in park.   My understanding is 12.2V is around 50% charge for a AGM Battery and it’s okay letting it drop to this  level of discharge and still expect an acceptable life from the Battery.  Regular lead acid batteries may need to be charged at a higher voltage.  
 

You can find some useful information on batteries at this link plus plenty of others https://www.energymatters.com.au/battery-voltage-discharge/

[Corolly Poly]

6 minutes ago, JasonM said:

I tend to put the car in park and charge for 30-45 min once every 2-3 weeks anyway. If the voltage drops to around 12.2V or below I generally give it a boost in park.   My understanding is 12.2V is around 50% charge for a AGM battery and it’s okay letting it drop to this  level of discharge and still expect an acceptable life from the battery.  Regular lead acid batteries may need to be charged at a higher voltage.  
 

You can find some useful information on batteries at this link plus plenty of others https://www.energymatters.com.au/battery-voltage-discharge/

Is yours AGM. I thought they were lead-acid as standard

[JasonM]

I believe it’s an AGM Battery for the 2.0L as Battery is in the boot, or maybe it’s a lead acid sealed type.

[Corolly Poly]

24 minutes ago, JasonM said:

I believe it’s an AGM battery for the 2.0L as battery is in the boot, or maybe it’s a lead acid sealed type.

Be good to know.  I don’t set my Ctek to AGM. Thought it was lead-acid

[yossarian247]

11 hours ago, JasonM said:

I believe it’s an AGM battery for the 2.0L as battery is in the boot, or maybe it’s a lead acid sealed type.

No, Toyota only fit conventional flooded maintenance-free batteries to the Corolla even when the Battery is in the boot. The OEM Battery is the identical on the 1.8 and 2.0. 

It used to be the case that Toyotas with the Battery located inside the passenger compartment were fitted with AGM batteries but that ended with the Auris apparently. 

As I mentioned somewhere on another thread, I removed the OEM battery on my 2.0 estate some time ago, I still have it in the garage, and I can tell it clearly has liquid inside. An AGM battery wouldn't. 

[JasonM]

That’s very helpful thanks.  May I ask what you replaced your Battery with, I assume it’s a size 27 AGM Battery?  Did you notice any improvement in keeping the charge?  

[yossarian247]

13 hours ago, JasonM said:

That’s very helpful thanks.  May I ask what you replaced your battery with, I assume it’s a size 27 AGM battery?  Did you notice any improvement in keeping the charge?  

It's a UK size 012, I replaced it with another flooded lead acid Battery but a Varta Silver which is 54Ah (the original Battery was 45Ah).