what is a full leisure battery?

[dunky bongo]

I have seen a lot of posts regarding leisure batteries and my understanding is that a full leisure battery will be at around 12.7v.
I have recently purchased a CTEK charger which maintains the fitness of the battery while my beloved sits on the drive... without going into the techy stuff that frankly baffles/bores me, I would like to know why the charger charges to 14.4v but within a short period of time the battery charge shows 12.8v, is this correct or is there either a fault with the battery (which is brand new) or a possible [earth?] leakage.

Any advise would be greatly appreciately before I embark on a 800 mile round trip to Wales next weekend.

many thanks
Duncan

[moonshine]

Everything sounds just fine to me. if the battery maintains this voltage then all is well. The charger voltage will start high, and then fall as the battery reches a full state of charge.

[dunky bongo]

my only other concern is I bought one of those ciggy lighter adapter things so I can plug multiple gadgets into the electrics, I thought I was being clever by buying one that has coloured LEd lights to indicate battery condition but I suspect it's making me paranoid.
The elec point is wired to the leisure battery and although it will show all 4 light (red, 2x orange & green) immediately after charging once the battery 'relaxes' it goes down to only one orange and red, is this normal too and have I been sold a pup?

thanks
D

[John the sparky]

when your bong is running you will probably get 13.6 to 13.8 V at the battery from the alternator (I think, but happy to be corrected )

so your 'gadget', if like the one in my car, will show full voltage when the car is running and being overcharged (sort of)

I haven't got a leisure battery, so am not fully up on charging systems (arse always worn out of a tailors trousers etc )
but I imagine you charge the vehicle battery as normal, and run a sort of solid state charger thing that senses when vehicle battery is Ok and then charges the leisure battery, but the two batteries like to be charged differently so the box will do something clever, so I imagine it isn't just a switch.

but if the leisure battery charging from the alternator then it is designed to give a constant voltege for a long time (about 12.7v I think )... which would therefore not give a full chage light on your 'gadget'





phew..... sorry for that.... so in essence....YES, I think it's normal



John

[scanner]

Simplistically speaking, think of the battery as a water tank and the wire going into it as a hose connected to the bottom of the tank.

To fill the tank the pressure in the hose (let's say 14.4psi) has to be higher than the pressure from the water sitting in the tank (let's say 12 psi) or the water won't flow up into the tank and fill it.

But as soon as you turn off the pump that is supplying the water pressure, the pressure in the pipe drops to that caused solely by the new, higher level of water in the tank (let's say 12.7psi) - which has to be lower than the 14.4psi previously supplied by the pump.

So the battery is full when water pours out of the top of it - Q.E.D.

[missfixit70]

So where does the hose plug into the battery

[scanner]

At the RED terminal of course.

[John the sparky]

that's got me too........

I alway thought the hose was full of smoke, and whenever anything went wrong, it was the hose splitting... hence the smoke


surely the water would affect the smoke


John

[scanner]

surely the water would affect the smoke

Only if you are using Hubbly Bubbly pipe and waccy baccy - Maaan.

[missfixit70]

I wasn't thinking the same thing at all, honest

[dunky bongo]

Thanks everybody, good to know the nut houses still have some work to do in rounding us all up

[missfixit70]

Gotta catch us first

[smartmonkey]

12.8V indicates a very healthy battery as long as it's been a few hours since it was charged.

It will drop rapidly down from charging voltage to 12.8 as soon as you stop charging.