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Lithium Batteries


Terence Thatcher
This essay was just noted at Attainable Adventure Cruising. I don't use thes batteries, so I have not yet read it. But I know some others here do. Thought you might like to read it.


Thanks Terry. Interesting article. I don’t know much about lithium batteries other than that they are batteries and supposed to be better than the ones that have been around forever. I am definitely interested in learning more but all the technical stuff about them is way above my head. But it does read as though the author is mainly focused on lithium ion which from the very little I understand is a different chemical makeup from the popular lithium iron phosphate style that seem to be the most popular for marine, rv, and ev applications. Hopefully some members here that know more and are currently using them can comment on what they have learned and personal experience.

Warren Holybee

Active Member
That article misses a lot. Not making the distinction between Lithium Iron Phosphate, and Lithium Chemistries is a huge miss.
Lithium Iron Phosphate do not enter thermal runaway. In fact, if you set them on fire, they will go out on their own, and only burn while something else is burning them.

Lithium batteries are made out to be more complicated than they really are. You need to make some special accommodations, but once done they are maintenance free. You can't damage them by partial charging like Lead Acid, you don't need to get them to 100% every few days Like Lead Acid, they are not damaged by using more than 50% of the capacity like Lead Acid. The BMS protects against over and under charging, so that won't damage them. If you start with a good LFP battery and install it right, they are actually much easier in every way that Lead Acid.

The only provisions that need to change are that they charge at different voltages and rates than Lead Acid. So chargers need to be updated, and cheaper "stock" alternators can't deal with the high charging currents so they need updated or some other protection for them installed.

My LFP Battery is 300Ah, and I can use all of it. It replaced 2 Group 31 batteries totaling 230ah, of which only 115Ah could safely be used. So almost triple the capacity. The LPF is the about same size as the 2 Group 31s, and weighs half what the 2 group 31s did.
While I don't have or even know much regarding Lithium Batteries.
The article seemed to lump everything and every problem into on mess. Seemed to "Miss the Boat" so to speak. Nigel Calder's "rebuttal" was interesting too.