Upgrade from AGM to Lithium Batteries: The Complete Upgrade Guide

If you’re thinking of upgrading from AGM to lithium batteries (LiFePO4), you’re making a great choice! Lithium batteries are lighter, last longer, charge faster, and give you more usable power. Whether you’re using them for off-grid setups, caravans, boats, or solar power systems, switching to lithium can make a big difference.

But before you make the switch, there are a few things you need to consider—like choosing the right charger, installing them correctly, and ensuring safety.

In this guide, we’ll cover:

• The key differences between AGM and lithium batteries
• How to install and mount lithium batteries safely
• Choosing the right battery charger and monitor
• Safety tips and ventilation needs
• Why battery cell quality matters

By the end, you’ll know exactly how to upgrade to lithium batteries safely and efficiently!

Why Upgrade from AGM to Lithium Batteries?

Lithium batteries offer some serious advantages over AGM. Here’s why so many people are making the switch:

• Longer Lifespan – Lithium batteries can last 5 to 10 times longer than AGM, with up to 5,000 charge cycles.
• Lighter Weight – They weigh 50-70% less, making them perfect for RVs, boats, and mobile setups.
• More Usable Power – You can use 80-100% of a lithium battery’s capacity, compared to just 50% for AGM.
• Faster Charging – With the right charger, lithium batteries can charge up to 5 times faster than AGM.
• Consistent Power – Lithium provides steady voltage, while AGM voltage drops as the battery discharges.

Bottom line: If you want better performance, faster charging, and a longer lifespan, lithium batteries are the way to go!

1. Do You Need a New Battery Charger?

Not all chargers work with lithium batteries. Many AGM chargers don’t provide the correct voltage or have a float charge mode (which lithium batteries don’t need and can actually damage them).

How to Check If Your Charger Is Compatible:

Lithium batteries need 14.2V – 14.6V charging voltage (for a 12V system).
No float charging – Lithium batteries don’t need it, and it can cause overcharging.
Adjustable charging profiles – A good charger should have a “Lithium Mode” or let you manually adjust settings.

Best Chargers for Lithium Batteries:

Victron Blue Smart IP22 – Smart charger with Bluetooth monitoring.
Redarc BCDC Core 40A – Great for vehicles and off-grid charging.
Pro Tip: If your AGM charger isn’t lithium-compatible, replace it to avoid damage and ensure proper charging.

2. How to Install and Mount Lithium Batteries

Lithium batteries are easier to install than AGM because they don’t have to stay upright. You can mount them in any orientation, which makes them super flexible for different setups.

Installation Tips:

• Secure the battery – Use brackets or straps to keep it from moving.
• Avoid extreme heat – Keep the battery away from engine bays or direct sunlight.
• Use proper cables – Make sure your wiring can handle higher discharge rates.
• Parallel vs. Series – If using multiple batteries, follow the manufacturer’s instructions for safety.

Key takeaway: Lithium batteries are easier to install than AGM, but you still need to secure them properly and use the right cables.

3. Do You Need a Battery Monitor?

Yes! Unlike AGM batteries, lithium voltage stays steady until the battery is nearly empty, so a voltage meter alone won’t tell you how much power is left. A battery monitor helps you keep track of charge levels and power usage.

Best Battery Monitors for Lithium:

Victron SmartShunt – Connects to your phone via Bluetooth.
Enerdrive ePRO Plus – Shows real-time charge status.
Simarine Pico System – Great for detailed power tracking (RVs & boats).

Pro Tip: A battery monitor prevents unexpected power loss and helps you get the most out of your lithium battery.

4. Safety & Ventilation : What’s Different with Lithium?

Unlike AGM batteries, lithium batteries don’t release harmful gases, so they don’t need ventilation. However, safety is still important, especially when installing them in tight spaces.

Safety Tips:

• No venting needed – You can install lithium batteries in enclosed areas like under seats.
• Avoid heat – Install them in a space with good temperature control.
• Built-in BMS – A Battery Management System (BMS) protects against overcharging and overheating.
• Use fuses & breakers – Always install circuit protection to prevent electrical issues.

Key takeaway: Lithium batteries are safer than AGM, but proper installation and protection are still essential.

5. Why Battery Cell Quality Matters

Not all lithium batteries are created equal. The quality of the cells inside makes a huge difference in performance and lifespan.

What to Look for in a Lithium Battery:

• Grade A Cells – These last longer and provide stable power.
• Balanced cell management – Ensures equal charge across all cells.
• Reliable BMS (Battery Management System) – Prevents overcharging and overheating.
• Tested in real-world conditions – Avoid cheap batteries that haven’t been tested in hot and cold weather.

Pro Tip: Cheap lithium batteries with low-quality cells might fail early and not perform as expected.

Upgrade to Lithium Batteries in NSW, Australia

Switching from AGM deep cycle to lithium batteries is one of the best upgrades for off-grid power, caravans, boats, and 4WD setups. If you need a lithium-compatible battery charger, installation advice, or high-quality LiFePO4 batteries, Muller Energy has you covered.

Visit us at Muller Energy, 3 Cal Cl, Somersby NSW 2250, Australia, shop online at mullerenergy.com.au, or call +61 493 274 334 for expert advice on upgrading from AGM to lithium batteries today!