Electricity is so interwoven into our daily lives that we take it for granted — that is, until the next ice storm knocks out your power, or you can’t attend that Zoom meeting because your laptop is out of juice.
I often take my work on the road and so exactly 4 years ago, I found myself looking for a way to be powered for longer. My solution was to assemble a portable secondary lithium pack — and it’s a solution that is now more approachable than ever. Here’s how I did it.
Why Go Lithium?
Lithium can save you money in the long run. A Dakota 100Ah lithium battery will cost you about $900, whereas an entry-level 100Ah lead battery only costs $250. However, you can only discharge a lead battery to 50% or it will die prematurely. That means you need two 100Ah lead batteries for the same useable energy.
Next, you have to look at lifespan. A typical lead battery will last at most 500 cycles, while a lithium battery will last at least 2,000. You’d need to replace your lead battery four times as often. The equivalent utility you get from lithium would cost 2 x $250 x 4 replacements = $2,000 in lead cells! Do the math — lithium is less than half the price of lead in the long run.
There are also some lead AGM batteries that can last 1,000 cycles, but you’ll pay more accordingly.
![Dakota 100AH lithium battery - Dakota 100AH lithium battery -](https://s3.amazonaws.com/images.gearjunkie.com/uploads/2021/11/Dakota-100AH-lithium-battery--700x467.jpg)
Adding to the value proposition, lithium is smaller and lighter. In a van camper, every cubic inch is important. Lithium is 60% lighter than comparable lead batteries and 20% smaller.
Lithium can be charged faster and is much more shelf-stable — you don’t need to keep it on a tender. Lithium also performs better in warm weather than lead.
Why Not Go Lithium?
Cold temperatures can reduce the usable capacity of lithium cells, and they can’t be changed below 32 degrees. For that reason, most lithium cells should be placed inside the vehicle while lead batteries can be housed elsewhere in the vehicle chassis.
Note that if you have flooded lead cells, you should not install them in your vehicle, as they can emit dangerous hydrogen gas when overcharged.
You’ll want a special charger when using lithium in a vehicle, one that uses an isolated DC-DC converter. These can be slightly more expensive than the isolators used with AGM cells, but they’ll maintain a better charge and store more energy even on an AGM battery. The Victron 18A isolator we used is about $117.
Lithium cells are notoriously temperamental and require special charge and discharge circuitry. The Chevy Bolt battery fire debacle is a prime example of this. Those packs use lithium-ion cells made by LG.
For a secondary power system, you can choose the safer lithium iron phosphate (LiFePO4) cells which, while slightly heavier, are far less likely to catch fire. Lithium iron cells still need safety circuitry and charge protection, so it’s important to purchase them from a reliable manufacturer.
The Right Energy Partner
I stumbled upon Dakota Lithium at the Outdoor Retailer show back in 2017. Dakota was founded in the Pacific NW in 2008 and now offers an industry-leading 11-year warranty. As an EV systems engineer, I’ve built plenty of packs myself. It’s not rocket science, but there are plenty of ways to do it wrong.
So, I happily handed over $600 for 60Ah of lithium cells (the prices have dropped dramatically since then). I fashioned a rugged case for my cells and have since taken my Dakota pack on many extended camping trips and on-site customer visits. And I’ve even powered my refrigerator during an ice storm. It’s been a workhorse of a pack and so far doesn’t show any signs of degradation.
![Dakota Lithium Protection Dakota Lithium Protection](https://s3.amazonaws.com/images.gearjunkie.com/uploads/2021/11/Pack-1024x339-1.jpg)
Van Life Power Upgrade
![Dakota 100AH lithium battery - built Dakota 100AH lithium battery - built](https://s3.amazonaws.com/images.gearjunkie.com/uploads/2021/11/Dakota-100AH-lithium-battery-built.jpg)
Battery Management
![Dakota Lithium Dakota Lithium - Setup and Dashboard](https://s3.amazonaws.com/images.gearjunkie.com/uploads/2021/11/Dakota-Lithium.jpg)