How Big a Leisure Battery...

Hello - Been out for a few day trips since easing of lockdown and very pleased with our van that we bought in March.

I knew that the leisure battery was past its best so I tried charging it with a smart charger. It gets to a little over 12v but drops to a little under 11v after a day out. It's enough to work the taps and flush the loo but probably no good for the water or space heaters and no good for nights out.

It's a Numax LV22MF 75Ah 266mm long  x 175mm wide x 225mm high inc. terminals.

Has anyone managed to fit anything bigger or should I just replace it like for like?

Thanks

If the battery location is in the same position as mine - under the drivers seat - you will be limited to the length, width and height of battery.  Unless you want to relocate it to under the offside bench seat of course.

Can you fit anything bigger where it is situated? Large amp battery means larger physical size. If you can , just make sure the terminals don't touch the underside of the seat if that's where it lives. Check Tayna Batteries website for dimensions.

Thanks, I'll get the tape measure out. Just wondered if anyone had actually done it. 

On my Symphony (fore-runner to Symbol) I did manage to find a slightly bigger battery , 85amp instead of 75, by checking measurement on Taynas website. Couldn't fit anything larger. Only problem was in didn't have base shoulders for the clamps so I had to adapt one of the old-fashioned perforated bar with side screw rods found on classic cars.

I see they are showing a Lucas 80Ah on the Tayna site at a good price. It's slightly shorter than my Numax 75Ah but same height & width & 3 yr warranty instead of 2. The clamps in the box under the seat are adjustable so should fix securely.

Just seen an Enduroline 80Ah calcium battery with a 4 year warranty that will fit. Not sure if my Optimate 2 charger for 12v lead-acid batteries is suitable though. I'll ask on the Tayna website.

Thanks for helping.

Consider the quality of the battery as well as its claimed capacity. Our van is a 2012 Boxer so probably different under the driver seat. When we got the van it had 105AH battery that did not seem very good. I quickly replaced it with a 90AH Varta LFD on the advice of A and N caravan services. The chap also drew my attention to the limitations of our EC155 system. It can’t cope with more than 120AH battery according to Sargent. The Varta  was far better than the old 105AH battery. With that as encouragement I swapped out the single 90AH for two 60AH Varta LFD. Both fitted neatly under the driver seat. They perform very well and recharge particularly quickly when driving. As predicted though, the EC155 struggles to charge the two. What would take a couple of hours of driving takes three days on a hook up. So, consider also your van‘s electrical controller/charger. The EC155 is a lemon.
My batteries came from Tayna.

Timedout wrote: They perform very well and recharge particularly quickly when driving. As predicted though, the EC155 struggles to charge the two. What would take a couple of hours of driving takes three days on a hook up. So, consider also your van‘s electrical controller/charger. The EC155 is a lemon.
My batteries came from Tayna.

The time taken to charge a lead acid battery using the conventional three stages is dependant on battery condition, state of charge at the beginning, temperature and time. If a battery needs 8 hours to recharge, it will take 8 hours whatever you charge it with. If your onboard charger will not recharge a flat battery in 12 hours either it or the battery is faulty. You will only be able to replace about 15% of the charge with two hours driving.

Peter Brown wrote:

Timedout wrote: They perform very well and recharge particularly quickly when driving. As predicted though, the EC155 struggles to charge the two. What would take a couple of hours of driving takes three days on a hook up. So, consider also your van‘s electrical controller/charger. The EC155 is a lemon.
My batteries came from Tayna.

The time taken to charge a lead acid battery using the conventional three stages is dependant on battery condition, state of charge at the beginning, temperature and time.  If a battery needs 8 hours to recharge, it will take 8 hours whatever you charge it with. If your onboard charger will not recharge a flat battery in 12 hours either it or the battery is faulty.  You will only be able to replace about 15% of the charge with two hours driving.

Not strictly true. During the initial constant voltage phase (up to around 70% charge) a higher current charger will be a lot quicker and if you are charging two batteries then you want at least 10 amps otherwise it will take a long time. The other issue with two batteries in parallel is that if they are not perfectly matched then the internal impedance will differ so one could charge quicker than the other. For a flat battery it could take 24 hours to fully charge.