Here are the specs, price, and performance curves on RELiON
12 volt/100 Ah lithium batteries that work both as a Starter and a Deep Cycle battery.
Note that the battery weighs slightly less than 30 pounds and has smaller size dimensions that an AGM one. Also, it gets nearly 14,000 cycles at normal discharge usage rates. Apart from being smaller and much lighter than wet cell or AGM, plus having 10
times greater cycle life, the thing I like best is that these batteries produce their full rated discharge voltage throughout each usage cycle:
They make a variety of other batteries, both larger and smaller, including an impressive 300 Ah one, but it weighs 82 pounds which would make installation a multi-man task unless you are a hernia-proof gorilla.
Considering the ten-fold better cycle life, much lower weight, and greater efficiency, these LiFePO4 batteries pencil out at less than half the cycle cost of the older wet-cell or AGM ones which sure seems like a good deal to me.
Best of all, RELiON is currently offering a 15% “July 4th” sale discount on Web orders, using the check-out code FIREWORK
15 when you place your order!
14,000 cycles amounts to 1.9 cycles per day for twenty years, given you use your boat 365 days a year. Lead acid gives you only one cycle a day for twenty years under the same conditions. I’m going to say that cost / cycle that I am young enough to use as a leisure summer sailor may be considerably more for the lithium.
The other advantages are not to be sneezed at of course but the cost is ~4X flooded lead acid.
Here is a link to a “Marine How To” article on lithium batteries. A summary is that: the article was last updated in April of 2020, the ABYC has not published standards for lithium batteries in boats, some insurer acne companies impose limitations on their use in boats and of drop in replacement batteries at the present he is only recommending Lithionics G125 &G315 or Battleborn/Dragonfly Energy. He calls Victron and Mastervolt “Factory Integrated Lithium-Ion Systems”. In addition to the 300 pound gorilla installation problem How To recommends using 3 100 amp batteries hook in parallel instead of one 300 amp battery becasuse he says most drop in batteries do not have battery management switches large enough to handle the heavy current draw. He reports on a client that bought an 8D drop in replacement battery rated at 300 AH. It destroyed 3 alternators, and his inverter/charger. The specs for the battery revealed it was limited to 100amp discharge current and 50amp charge current. It was simply the wrong battery for the job.
Relion nor the new Trojan Trillium lithium batteries are mention in his article so I don’t know if he has had a chance to look at them yet.
Regarding charge cycles. Lithium batteries lose some capacity each year whether they are used or not. My research suggests that 10 -15 years might be the life expectancy of a lithium battery even if you don’t use it. Unless you are a full time cruiser the massive charge cycle ratings of lithium batteries maybe academic.
That seems to be a reliable article. It is full of disclaimers of its limitations and comes right out and says that they sell LiFePO4 batteries. It also says not to rely on them alone as a research source. Seems reasonably objective.
Alan, Corvus NS30C, BPYC Toronto