Lithium batteries

[hodgmo]

"I'd like to think that companies installing millions of dollars each have done their due-diligence." I'd like to think so too since I share the road with them. (I did some fire protection work for AC Transit many years ago and they seemed like a good outfit.) Anyway, I hope their due diligence effort was better than Boeing's initial one was when the 787 APU system (which used LiCoO2 batteries) was designed. And, of course, due diligence for onroad vehicles (like city buses) assumes fast egress is possible and that first responders are minutes away. A different due diligence is called for solo sailing across an ocean, doncha think?

Again, I’m not against Li-ion batteries, but users need to understand that they pose an intrinsically higher fire risk than lead acid, and their use in ocean boats is relatively new so early adopters are breaking new ground – which can be a good thing or perhaps a bad one.

Last year Bruce Schwab put it well: “Knowing that Lithium is great, but for the foreseeable future not for everyone, we want to have the next best thing [carbon foam grid lead-acid] as an option” http://sailinganarchy.com/tag/lithium/

[solosailor]

Anyway, I hope their due diligence effort was better than Boeing's initial one was when the 787 APU system (which used LiCoO2 batteries) was designed.

Agreed. I can't understand why they went with Cobalt outside of slightly higher energy density as they do off gas oxygen and turn into a blow torch. I was surprised their solution was a metal box to isolate them. Some early marine packs from a well known suppliers used Cobalt and there was a maxi that was burned badly and totaled.

Again, LFP and several other safe chemistries do not really "catch fire", they melt down. I've seen several melt downs of LFP over the years and none has resulted in a fire or loss of boat. The melt down happens when cells are overcharged. The way that can really happen is if there is an individual cell failure due to over-discharge. Then when the pack is recharge the 3 of 4 remaining cells try to handle the full charge voltage creating a 4V+ state in the remaining good cells. I've never seen a failure outside this scenario.