Lithium Battteries

Some may remember when I replaced my 400 Amp hour AGM battery bank with a single 130 Amp hour lithium battery.  The port hull came a 1/2" out the water with the removal of the weight.

I heard all kinds of criticisms. 

- that is way too small of a battery bank.  Answer:  With a lithium battery the voltage remains at 13.2 VDC until the battery is nearly depleted.  With a lead acid based battery, the voltage immediately starts to drop as charge is removed.  Once you exceed 50% loss, you are permanently damaging the batteries.  Not so with lithium. 

- Lithium batteries will start on fire and sink your boat.  Answer:  Marine batteries are a cross of lithium, phosphate and cobalt.  The Valence batteries have been tested, under full load, in a fire and shot with a 50 caliber bullet.  Still no explosion.   

- You need to change all of your charging equipment.  Answer:  Nope.  With the chemical makeup, listed above, the same charging parameters can be used.  Just need to change the acceptance and float voltage level.  On that note; it always amazes me the number of people who just replace their batteries, with similar type, and never check to see what the new batteries require for charging parameters.  When their batteries last 2-3 years, they don't question the cost to replace them again, but question me on the cost of lithium batteries.  

- Too expensive.  Answer:  My first battery, including the BMS (battery management system) and safety relay, cost me about $1500.  That may seem like a lot, but based on the 10,000 cycles (minimum), the battery will last longer than I will have the boat.  As noted above, no one seem to complain about spending $700-$1000 every 2-3 years.  I have had, my single battery, for 6 years.  Zero degradation in static voltage or capacity.  Three years were spent living aboard on a mooring ball with 60-100 amps drawn out every night (unless the wind was blowing).   

This past summer, my old starting batteries finally bit the dust.  Instead of replacing them with standard batteries, I rewired the boat to use my house bank to start the engines.  I then purchased an additional lithium battery (same model number), to double my house bank to 260 Amp hours.  Not really needed, but figured the extra capacity would ensure enough starting power after a night on the hook.  Found the battery, used (1year old), for $400.  Total battery weight is still under 50lbs. 

Since I was adding to the load of the BMS, I contacted Valence and they sent me the programming files to update the BMS.  I had to purchase $160 worth of stuff to do that.  When I had issues getting it to take, I called the engineer directly and he modified the program, on the fly, and we were successful.  That is customer service! 

Being an ABYC certified tech, I get first crack at their webinar's.  The latest Lithium batteries if what prompted me to write this blog.  I am sold on Lithium for boats, and have 6 years of use to prove their worth.  Don't just take my word for it.  

   https://www.youtube.com/watch?v=21Ql6n7nndQ



We are still enjoying Marathon.  Opening the keys have doubled our COVID cases, but there are still less people to contend with.  We plan to stay through the end of July at this point. 

Christmas photo, but with the 4th coming up, we plan to hang up the American Flag again.