Which sized lesuire battery?

[marlowswindows]

I think any battery needs ventilation so it can dissipate heat when charging. Never heard anyone insulating around a battery. ?

They don't like cold weather so just something to keep the edge off you can actually buy battery covers. So it won't do any harm the battery can stil ventilate

 

[ched999uk]

I think any battery needs ventilation so it can dissipate heat when charging. Never heard anyone insulating around a battery. ?

A lot of modern cars have insulated jackets around the starter batteries to protect them from the engine bay heat and the cold temp in winter. They do need ventilation though but that's not a huge amount of air flow - some batteries come with a small plastic tube to vent through.

 

[marlowswindows]

A lot of modern cars have insulated jackets around the starter batteries to protect them from the engine bay heat and the cold temp in winter. They do need ventilation though but that's not a huge amount of air flow - some batteries come with a small plastic tube to vent through.

I will take the lid off then. Not tight to the battery is the insulation so should be okay.just freezing in back of a van that's been sat since Friday.?

 

[ched999uk]

I will take the lid off then. Not tight to the battery is the insulation so should be okay.just freezing in back of a van that's been sat since Friday.?

As long as the vapours can escape then it should be fine.

 

[marlowswindows]

Used today for first time probably 4 or 5 hours work due to weather.

Went out battery was at 12.8v I've been home 3 hours now all 3 volt readers are showing 12.7v.

I'm happy at that. I've got a victron charger so will leave that in van and hopefully charge every two days.

Would you say 12.4v is 50 percent charged?

 

[ched999uk]

Used today for first time probably 4 or 5 hours work due to weather.

Went out battery was at 12.8v I've been home 3 hours now all 3 volt readers are showing 12.7v.

I'm happy at that. I've got a victron charger so will leave that in van and hopefully charge every two days.

Would you say 12.4v is 50 percent charged?

About 12.1 is 50% charge on a sealed Lead Acid - It does very depending on which chart you look at. 12.89v is 100% charge again varies of which site you look at.
AGM is a little lower on both.

 

[marlowswindows]

About 12.1 is 50% charge on a sealed Lead Acid - It does very depending on which chart you look at. 12.89v is 100% charge again varies of which site you look at.
AGM is a little lower on both.

I found that it varied so next best thing was you guys.

 

[spruce]

Used today for first time probably 4 or 5 hours work due to weather.

Went out battery was at 12.8v I've been home 3 hours now all 3 volt readers are showing 12.7v.

I'm happy at that. I've got a victron charger so will leave that in van and hopefully charge every two days.

Would you say 12.4v is 50 percent charged?

There are a couple of different charts that give slightly different values for each state of charge.

This one attached seems to follow my Victron Battery Monitor results pretty closely, so it's the one use.

When testing a battery's state of charge, we have to wait at least 4 hours before checking the battery voltage. During that time, the battery needs to be fully rested. When arriving home, my battery will show a voltage of 13.3 or 13.4v because of the residual charge still in the battery and needs those 4 hours or more to completely dissipate.


The chart shows 12v as completely flat. These are at rest voltages, which are different to voltages under load. For example, Spring controllers are factory programmed to switch off at an under load voltage of 10.4/10.5v. Our Webasto diesel heater and other diesel air heaters do the same. 10.4v is considered to be flat when the battery is under load. Once the load is removed, the battery can quickly return to a voltage indicating a 50% state of charge. I experienced this myself a few years ago with my diesel heater and a 5-year-old leisure battery.

When a battery is new, a fully charged leisure battery charged with a smart charger should also be the capacity of the battery. When the battery starts to age, (or wear out), its capacity reduces. So you can have a fully charged old 110 amp battery reading 12.7v or above, but only have a capacity of say 20 amps. That 20 amp capacity would still keep our pumps running all day with the odd bit of alternator charging during the day, but add a load, such as our diesel heater, and the power needed for that will show the true state of that battery, capacity wise.

ps. I don't know what happened here, but I lost a whole lot of my response after this.

 

[marlowswindows]

Happy with my set up now I've done a day and a half's work since putting it in fully charged. Last night it was showing 12.7 after 3 hours stationary.

Today full day fair bit of driving 4 hours rested showing 12.7v so for me split charger does help if I can get another day with out charging I will be very happy

 

[spruce]

Re: Battery boxes.
I have my leisure battery mounted on the frame on the side of the tank. It just means that the battery isn't sitting on the freezing van floor like it did with my previous van. I do have a cover across the top which protects the terminals of the battery against being shorted out with metal or carbon fibre.

 

[marlowswindows]

Think it's time to lock this post now I'm sure your all getting fed up with my nightly updates.

Hopefully good reading content for people