The new trend in leisure batteries is upon us and unless you are an early adaptor then you will be wondering what all the fuss is about and are they worth the big bucks for one of these Lithium LifePoo batteries – it’s LiFePO4 actually, I made that mistake first off!
Across all markets over recent years Lithium-ion batteries have been gaining in traction. To the uninitiated it is easy to dismiss Lithium-ion as an expensive alternative to VRLA (valve regulated lead acid) technologies such as AGM (absorbed glass mat), if simply looking at the amp-hour (Ah) rating. I mean a decent 100AH battery would set you back under £150 and a LiFePO4 version around £700.
This was the initial mistake I made a few years back. Digging deeper it became clear to me that there is a lot more than Ah ratings to consider, when choosing the best batteries for your application and this is why you should be open to Lithium batteries for your next battery investment.
Let’s tackle some of the jargon around batteries before we dive into whether a Lithium LiFePO4 battery is good for your little travelling beauty.
You will be familiar with volts as your batteries in your vehicle will be 12v. The volt is often referred to as electrical pressure and this is where the water/plumbing analogy starts when referring to these electrical terms. Think of your battery as a pump that pushes voltage around the electrical system in your vehicle. Lithium batteries are no different – they come in 12v and 24v versions.
The batteries in our vans are rated in AmpHrs so we are familiar with the term but what does it mean? Amp hours is a unit of energy, which can be consumed or generated over a period of time. So if you have a total consumption of energy of 10A per hour of the gadgets in your van – then your 100Ah leisure battery will last 10hrs – wrong! It’s 5hrs but don’t get confused, this is because your 100Ah battery should only be discharged to 50%.
Depth of Discharge (DoD)
This is how far you should discharge your battery before needing to re-charge it – although you may have a 100Ah battery you will only have 50Ah available to use before you start damaging the battery. The Depth of Discharge (DoD) refers to how much energy is cycled into and out of the battery on a given cycle, expressed as a percentage of the total capacity of the battery. Although this varies cycle to cycle, the maximum depth of discharge for lead acid batteries is typically at or below 50%. This is where the Lithium battery benefits start to come in. Lithium batteries discharged to 50% as other batteries last much longer but they can safely be charged to 100% making your 100Ah battery a true 100Ah battery (effectively doubling your battery bank).
Here we are referring to the number of discharge / charge cycles the battery can handle before you start loosing performance and the capacity drops below 80% of its rated capacity. This is where Lithium wins. A typical leisure battery has around 500 lifecycles – pretty impressive for a battery costing less than £100. However the equivalent Lithium battery would have over 7000 lifecycles at 50% depth of discharge and 2000 lifecycles at 100% depth of discharge. At 7 times the price the Lithium battery is still 50% cheaper over the lifetime of ownership.
Switching to Lithium Leisure Batteries (LiFePO4)
After all that – is it worth investing five, six or seven times the amount in batteries to switch over to Lithium. If your set-up is correct in the van and you ahve the budget then I would say yes and her’s why.
The main advantage to lithium is the massive life cycle rating. Our TN Batteries are rated at 7000 life cycles at 50% making this the highest life cycle battery I’ve seen. Also, you can discharge the batteries to 100% DoD and still get 2000 life cycles, so you are actually get a pure 100AH battery.
Another advantage of lithium is that these batteries do not sulfate over time, which means you can leave it for six months and use it as new where if you were to leave a conventual lead acid battery it will sulfate wont work. This tends to happen with a lot of customer with caravans / motorhomes because it is seasonal. Getting a Lithium battery will solve this issue.
The final factor to consider is weight – Lithium batteries are much lighter than their counterparts, so in smaller vehicles this can be a huge advantage.
Other advantages are:
- Using the technology of lithium iron phosphate cell, superior safety, thousands of cycles, 100%DOD, under normal conditions
- Built-in automatic protection for over-charge, over discharge, over current and over temperature
- Free of maintenance
- Internal cell balancing
- Lighter weight: About 40% ~50% of the weight of a comparable lead acid battery.
- Can be charged using most standard lead-acid charges (set)
- Wider temperature range:-20℃~60℃
- Support for Series application expansion (up to 51.2V) and two in parallel