Replacing Starter and Leisure batteries.

[colin]

Must get down to doing this as both are past their prime.

Present set up, standard Ducato 90AH starter battery, EBL99 and 85w solar (with basic PWM) going to Banner 92AH AGM leisure battery. This set up has served well for the last 8 years, but we now both have electric bikes so am looking for a little extra capacity. With our usage driving and solar has easily kept the battery up to charge for most of the year, even in winter it would probably be ok but we tend to go for EHU and use electric heating.

So with that in mind I'm looking at a good quality starter battery, Alans idea of using a LFD90 with it being 'deep discharge' when not in use sounds good.

For the leisure battery a small up grade would be good, so I'm thinking 2off LFD75's as these will fit under seat, give extra capacity and not over burdon the charging, I could go to 2off LFD90 but don't really need that much. I would then run this with the present solar charge controller for a while to see how it works out, with the view of changing to something a bit better if needed.

Does this sound sensible?

 

[StuartO]

If I understood Allan’s advice correctly, the risk in increasing leisure battery capacity is overloading the mains charger in the EBL99. But you can add a Schaudt suplementary charger, at a price, to eliminate this risk.

 

Another consideration is weight. By replacing with two LFDs you will take a sizeable extra bite off you payload - and do you really need to do this? With solar panels I find that my leisure battery tops up every day when touring so I didn’t really need the second LFD90 I’ve got and I should really take one out. Whether you should do this too depends on you usage and whether you discharge enough each night to bed two leisure batteries.

 

Maybe you should think about optimising your solar outfit by fitting a better regulator before you spend money and payload on double leisure batteries.

[colin]

At the moment our usual driving and the solar panel means the batteries are rarely less than full when we need them in the evening, so if we need to put a bit in bike batteries in the evening just changing to a MPPT solar controller will be no help. One reason with going to 2off LFD75's is this gives roughly a AH of 10 times the charge rate of EBL99 which AFAIK is the max recommended.

p.s. one reason for having 2off LFD75's as opposed to 2off LFD90 is also they would weight less.