Club 80-90 Forums

Oh dear, I let my fancy Lucas leisure battery go totally flat (left summat on by mistake ) stupidly I have a low voltage cut off, but I had left it in by-pass mode so it might as well not have been there

I have got it on charge, but I really like to be able to rely on my leisure battery, so looking around at new ones.

Of course technology moves on, the newer "calcium" batteries (etc) offer more re-charge cycles but they also need a higher charging voltage. This is no big problem as you can get for £12.50 a 14.5 volt regulator pack for your alternator (15 mins to fit) as per ebay item number 251011068735 (I just bought the last one off that supplier )

My thought was = how will my older technology starter battery react to getting 14.5 volts (instead of the 13.8 I guess it was designed for)

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Interestingly, the guys at Alpha Batteries tell me that their "deep cycle" batteries can only stand the normal 50% "flattening" - I thought they could stand a "deep discharge" but apparently it means they just offer more discharge / re-charge cycles = worth bearing in mind.

btw, I am not going down the trojan route.

I will likely buy one of these HERE 125AH @ £90 (btw, mine is not fitted under the front seats). And disconnect the "bypass" switch on the low voltage cut off !!!!!

Not looking for any answers or owt = just a blog this is

ghost123uk wrote: My thought was = how will my older technology starter battery react to getting 14.5 volts (instead of the 13.8 I guess it was designed for)

It should be ok how old is the battery???

jamesc76 wrote:

ghost123uk wrote: My thought was = how will my older technology starter battery react to getting 14.5 volts (instead of the 13.8 I guess it was designed for)

It should be ok how old is the battery???

Dunno - it was in the van when I got it a year ago - holds a good charge - not screw on caps ( ) but looks old school design...

I suppose I could lift it out and get a make, model and date code

most battery's dont last much more than say 10 years so "modern charging systems" have been about that long so should be ok, just watch out for gassing!

Just doing a bit of tidying up of wiring, sorting out a better arrangement for the programmable low voltage cut off, and I checked the current that it uses. It uses 45mA just to monitor the state of the leisure battery, not too bad, but add to that the 50mA the radio memory feed uses and we have 95mA. Still no big deal, but...

ghost123uk wrote:My thought was = how will my older technology starter battery react to getting 14.5 volts (instead of the 13.8 I guess it was designed for)

Original Bosch/Beru regulator charge tollerance was 13.9 - 14.2 volts (I have it in my little VW mechanics hand book) so 14.5 isn't that much higher. Chances are if that old battery hasn't got removable tops it's a Calcium/silver calcium already....they have been around for at least 10 years already.

Martin