New Batteries – Trojan T105’s
When I was building the van I snapped up some cheap leisure batteries that were on sale. I didn’t really look any further than the capacity at the time, this was stated at 110Ah. What I didn’t realise is that there is a huge difference between good and bad leisure batteries. After a 2 month trip in the van I noticed that the batteries seemed to be discharging more quickly than their capacity would suggest, I did a bit of research and came across this article. In the article they show the test results for various leisure batteries, some batteries achieved less than 50% of their rated capacity! As mine were the cheapest of the cheap I doubt they would have scored too highly on the test. The weight of the battery is also an indicator of quality, I took mine to the scales and they weighed in at 22kg each, the labels stated 27kg so they contain a fair bit less lead than they should.
After discovering my batteries weren’t great I started researching replacements. Trojan are widely regarded as one of the best battery manufacturers for lead acid batteries. Their T105 batteries are made with deep discharge in mind and they are often found on golf carts. Some of the stats that convinced me of their worth are below.
Max recommended depth of discharge
Trojan T105 – 80%
Most leisure batteries – 50%
Number of cycles to 50% state of charge
Trojan T105 – 1200
Most leisure batteries – around 80 for a bad battery – 400 for a good battery

As you can see from the graph even discharged to 80% the Trojans still get 400 cycles. This means that you are getting loads more useable battery capacity than a standard leisure battery. They will also last years longer due to the high number of cycles they can survive.
Once I’d looked at the statistics my mind was set on Trojans, I ordered 2 batteries (they operate at 6v each so you need to by them in multiples 2 to use at 12v) The best price I found was Plymouth Batteries on ebay who had a two for £245. They arrived on a pallet a couple of days after my order.