Find a retailer
Back to articles

Upgrading from AGM to Lithium Deep Cycle batteries


First of all, if you’re planning on charging your Lithium battery (or batteries) from the vehicle’s alternator whilst you’re driving, you’re going to need a good quality DC to DC Battery Charger which has a built in Lithium charging profile.

Lithium batteries have huge charge acceptance – for Century Lithium Pro it’ll happily accept up to 100A - and the role of the DC to DC charger is to regulate the charge (or current) which flows from the vehicle’s alternator and starting battery to the Lithium battery, firstly to ensure it doesn’t overwhelm the alternator or starting battery, but also to apply a Lithium charging profile. This Lithium charging profile optimises the charging cycle to prolong the life of your batteries.

Ideally, your DC to DC Charger would also have two (2) inputs, so that you can charge your battery from the vehicle whilst your driving, but also from solar panels once you’ve stopped.

Secondly, if you’re planning to take advantage of Lithium’s greater charge and discharge currents, 100A in and out in this case, you’re going to need to upgrade your cable sizing to suit. If your cables are undersized for the current they are expected to carry, they could potentially cause a fire. And if they’re oversized, you’ll get voltage drops.

We’re not going to get into cable sizing in this video – but there are plenty of guides on the internet to help you determine the cable size you’ll need depending on the maximum amperage they’re going to carry.

You also need to remember it isn’t just the cabling for the charging side which needs to be looked at. Your new Lithium battery system will also allow you to power many more devices all at once – so you may need to look at having extra power outlets wired in, and again ensure all the cables for these are appropriately sized.

And lastly, if you need the capability to recharge your batteries outside of the vehicle individually, you’ll also need an appropriate battery charger which includes a Lithium battery charging profile. Lithium batteries are very different from AGM or other deep cycle battery technologies – and under no circumstances should you ever recharge one using a regular AGM or lead-acid battery charger. If there’s a lithium manufacturer out there saying you can do this – I would be questioning the design and safety of the battery in question.

As always with Lithium - When in doubt, consult a professional as there is potentially a lot at stake here.

More from the Battery Hub

This site, like many others uses cookies to function and make your experience better. Find out more about our use of cookies in our privacy policy here.