Lithium all the rage

It’s fair to say lithium batteries are taking the RV world by storm, with as many as 2500-plus, mostly top-end off-road caravans and campers in Australia now powered by the latest, super-efficient portable energy source.

But if you’re like the majority of RV travellers, sticking mainly to the blacktop and never too far from a caravan park, the steep premium you pay for lithium technology is a “complete and utter waste of money”, according to one major supplier of lithium battery systems to the Australian RV market.

“We spend more time talking people out of lithium than talking them into it,” claims Queensland-based 

Enerdrive director Chris McClellan.  “It’s not a battery for everybody.”

“Lithium adds a lot of money to a caravan, and if it’s being used for what 70 per cent of vans are built for, towing behind a common wagon or sedan, moving through the day and then getting to the park and plugging into power, you do not need lithium, at all.

“(Lithium is) expensive, it’s excessive, it does not achieve any benefit (for touring vans).”

McLellan says the greater efficiency of lithium batteries, which include lower discharge rates, faster recharging and a greater charge cycle life, is most relevant to hard-core off-road campers running big battery systems and inverters that run energy-hungry appliances like large fridge/freezers and air-conditioners.

He says it also makes financial sense for those camping for extended periods ‘off the grid’ and for "overweight" off-road caravans looking to shed up to 100kg or more by using smaller, lighter lithium batteries.

“In a decent off-road caravan your heaviest weight is your batteries, and if you change to lithium you’re reducing your battery weight by 40 to 50 per cent…”

He says Enerdrive’s customers including

Bushtracker, Kedron,

Australian Off Road, Halen Vans, Free Spirit and Trakmaster “build heavy, solid- set caravans that genuinely go off the beaten path and don’t go anywhere near the grid again.

“They’re reliant on solar and generators for recharging, have the inverters and might want to run coffee machines and that type of thing, that’s the real market for lithium.”

The extra cost of installing a lithium battery system is also easier to justify in a six figure priced caravan.

“In that size and cost of van, if you wanted to do a fresh install it would add around $2000-4000 to the installation cost, depending on what you go for and how extreme you do it.”

“In a $120,000 van that’s nothing. And you notice the savings in weight and space it in that type of van. But in the average Ma and Pa tourer, I would do everything I can to talk a customer out of lithium.”

Instead, he often recommends an upgrade of a van’s existing AGM system for those who feel they’re “running out of batteries”.

“I’ll tell them you probably don’t have enough charging on board. So instead of buying an expensive lithium system, put some more solar panels on the roof, probably put another AGM battery in...

“Up-spec your existing system before you even think of lithium, because lithium is not a retro-fit product (due to requiring a dedicated charger).”

“The only exception (for on-road vans) is if you were going to a (national) park for a couple of weeks at a time and you were reliant on your solar, then there’s a massive advantage to lithium.”

However, David Nielsen from

Revolution Power Australia, another major supplier of ‘turn key’ lithium battery systems that incorporate the

latest Redarc lithium battery chargers, says retro-fit as well as original-equipment markets could take off with the imminent release of a new Redarc battery charger that will be compatible with most types of deep-cycle batteries including lithium.

“From a (RV) manufacturer’s point of view it will be fantastic because they can fit it from the factory regardless of battery type and for most people it will be a simple upgrade (to lithium at a later stage) if they want to," he explained. 

"The manufacturers will be able to put one (battery charging) system in all caravans and it doesn’t matter what battery type the customer wants to go with.”

Both Enerdrive and Revolution admit to “massive” growth in the uptake of their lithium battery systems over the past 18 months, driven by both off-road RV and 4x4 users.

To date, Enerdrive claims to have fitted around 700 units whereas Revolution, which supplies to Trayon Campers,

Complete Campsite and Seachange Caravans, puts its latest count at almost 500.

Another early adopter of lithium, NSW's Kimberley Kampers, claims to have fitted more than 1500 lithium systems to its off-road campers and caravans.

Some manufacturers like Queensland’s Bushtracker now almost exclusively fit lithium, with “98 per cent” of all Bushtracker vans built powered by Enerdrive lithium systems according to Bushtracker’s Mathew Kurvink.

However, both Enerdrive and Revolution agree that increasing world-wide demand for lithium, which is a metal and therefore a finite natural resource, will prevent any significant price drops in the short term at least.

“They’re not going to get cheaper. We struggle at the moment for supply,” said McClellan.“It could actually get to the point where we see a lithium shortage in Australia.”

WHAT’S THE FUSS ABOUT LITHIUM?

Lithium-ion deep-cycle batteries offer a number of advantages over the more conventional lead-acid AGM batteries fitted in most caravans and campers, says Revolution Power Australia’s David Nielsen.

Not the least of these are being up to a third lighter and smaller in size.

“A typical 120Ah AGM weighs between 30-35kg. Our 100Ah lithium battery is 11.9kg, but that’s equivalent to a 200Ah AGM, because you can use 80 per cent of the battery,” he explains.

“With an AGM you shouldn’t use any more than 40 percent… so that’s how we can basically say it has double the capacity.”

As a result “you only really need one 100Ah (lithium) to be the equivalent of two 120Ah (AGM) batteries, but most people are still going with two, 100Ah lithiums so they’re getting a lot more power.”

Other benefits are improved cycle life and faster recharging.

“You’re looking now at 2000-3000 cycles (with lithium) compared to 200-500 cycles (AGM).

“A 100Ah lithium with the Redarc DC-DC charger will recharge in two hours from dead flat, which you can’t do with any other battery. An AGM will be at least 12 hours to get it charged properly…

A lithium battery also holds maximum voltage longer than an AGM battery.

“They hold their voltage all the way to the end, so as the battery power comes down the voltage stays up.

"Also, what happens with a lot of 12V appliances like fridges is once the battery starts to drop in voltage the fridge will draw more. It will go from drawing 12 amps to drawing 16-17 amps out of the battery to try and keep it there, whereas with lithium it will keep it there all the way to the end.”

Lithium also captures solar energy more effectively, he says.

“Lithium loves solar. It has a low internal resistance whereas an AGM has a high resistance, so solar has to try and push its way in.

"So if a solar panel is putting out seven amps, you may only be getting three to four amps going into the battery (with AGM). With lithium it’s like a slippery slide… it basically just sucks it in.”

The lithium iron phosphate (LiFePO4) technology used for RV deep-cycle batteries is also a more stable product than other types of lithium products.

“Our batteries are LiFePo4, which is very safe. (The lithium) that brought planes down and blew up all sorts of things, that was lithium cobalt, that’s the volatile one. You’ve got to keep it cool and in dry conditions.”

The Revolution batteries are also 'splash-proof''.

“Our batteries are IP54 rated, so if they go under water they just turn off, whereas a normal battery would just keep bubbling away… they keep looking every few seconds until it’s safe to come back on.”

Disadvantages of lithium include the requirement for a purpose-designed charger and other ancillaries, limiting its appeal to the DIY and retro-fit markets. Although the recent introduction of  “idiot proof" complete, drop-in systems from companies like Revolution and Enerdrive is certainly making lithium more accessible and user-friendly.

Then there’s price, with Revolution’s smallest 60Ah ‘turnkey' system starting from $2000 and rising to almost $5000 for a 200Ah system.

“It’s still a big jump (pricewise) but it’s a lot cheaper than what it was five years ago,” Nielsen says.

However, industry claims that lithium-ion batteries pay off in the long run because they last longer (from 10-20 years versus 2-3 years for an AGM battery) remain contentious. 

“We don’t even use life of the batteries as a selling point,” says Enerdrive’s Chris McClellan.

“We don’t promote it because the simple reality is lithium-ion technology as we know it today has only been commercially available for five years, and you can’t advertise a 10 year warranty when the product is not up to that life cycle yet.”