One of my regular jobs in the engine room is to check and maintain the battery bank.
I use the more usual 'wet' lead acid 110 amps hour batteries for our leisure-side; we have 6!
I check the levels of acid and fill with distilled water where necessary. This appears to often be the case after a period where the charger has worked hard to bring the batteries up to the 13.7 volts level. Putting in 60 to 70 amps up to 14.8 volts appears to lessen the levels.
These batteries are now about 5 years plus old - so are doing quite well!
With 6 x 12v leisure batteries, there is wiring everywhere!!
More topping up of the electrolyte levels - using distilled water
Topping up the 2 x 12v engine start batteries - these are in series to give me 24v for the rather large (lorry) starter motor
Showing one of the 2 MegaPulse electronic gizmos wired across the battery bank
Showing the front of the 'MegaPulse'. This piece of electronic kit originates from Australia and is apparently used by their forces and emergency services.
Basically it checks the batteries and sends a micro-amp pulse across the terminals to de-sulphate the lead plates. Hence prolonging battery life!
Seems to work as we have had this set of batteries since Winter 2010 - admittedly we have been on hook-up for much of that time! - but, hey, extending battery life can't bad!
Incidently, I also used one of these on our motorhome leisure batteries
Last job whilst on this side of the engine - releasing any residual water from the in-line diesel filter for the Webasto. Happily, all is clear!