Lithium Batteries vs AGM Batteries - Which Is Better?



Andy here, and lately I’ve been getting questions about the difference between the lithium batteries and the AGM BRS Super Battery… 


But before we get into the differences between the 2 batteries,  you might be wondering why you should listen to me… 


In the late 80’s I began my career in the mining industry as an assembly mechanic where I would go underground and troubleshoot and fix equipment that was down.


I ended up becoming one damn good mechanic which led me to a new job teaching hydraulic, mechanics, and electrical classes to other mining equipment service technicians. During this time I saw every problem you could think of when it comes to heavy equipment issues and batteries…


Fast forward to 2003 – that’s when I started BRS Battery Ltd… specializing in rejuvenating and servicing locomotive and industrial batteries… I have pretty much seen everything you can think of when it comes to batteries… 



With all that being said, I want to give you my opinion on the Lithium Battery vs. AGM Battery debate… 


First things first, I want to start by saying I am a fan of lithium batteries, in fact I have lithium batteries installed in my boat and other toys... but today I want to focus on lithium batteries for power sports vehicles like ATV’s, Motorcycles, Jet Ski’s, UTV’s, etc… 

In my opinion the biggest advantage with lithium batteries is that they are lightweight, temperature resistant, provide more usable capacity, charge faster and offer zero voltage sag, there is no liquid in a lithium battery and they can  to be mounted in any position. 


Overall, lithium batteries are great but in my expert opinion it really depends on the application. 


AGM & Lithium Battery History


AGM batteries were developed in the early 1980’s and were first used in military applications to reduce weight and improve reliability.  



AGM batteries are known for their fast charging times, ability to deliver currents faster,  little to no sulphation, ability to handle deeper discharge without damage compared to a standard "wet" battery, minimum release of acidic gasses, and a potentially longer battery life.

Lithium Ion technology was developed around the 1970s - 1980s and was available for sale to the public in 1991 by Sony. 



Lithium-Ion batteries are known for their lightweight, fast charge time depending on cell configuration, and they are able to deliver up to about 95% of their capacity without a significant change in voltage. 

Both batteries are great however, here’s the big difference. 

If you live in area where you experience cold weather or long winters, you want to go with an AGM battery for your equipment and toys. 

Here’s why… 

Lithium-ion batteries work poorly in extreme cold because their electrolyte solvents become viscous or even freeze, which hampers the movement of lithium ions between the anode and cathode during charging and use.

The voltage delivery of a lithium battery is a very gentle slope followed by a plummet, whereas an AGM is a curve that steepens as the battery is approaching exhaustion. Good lithium batteries are very stable, with excellent internal circuitry, and dodgy lithium batteries are very volatile and, if you are using a cheap one under your seat on a motorcycle, some fire retardant undies might be in order. 



The Bottom Line

The bottom line is AGM batteries outperform lithium batteries in cold weather... So if you live in climate where it gets really cold -- the most reliable battery to have is an AGM Battery.  


If you want to upgrade to a supercharged high performance battery check out the BRS Super Battery Below