E-13 -- cells that comply

[crayiii]

Originally Posted by sailingharry

That's quite a firm. Every job requires updating the entire boat to way above current standards. Would they have required that same update if you'd simply replaced your AGM with new AGM? I would hope so, fire is fire and it doesn't matter what kind of battery you use.

I wouldn’t have used them for AGM replacement and they are booked out more than a year so I’m not sure they would take it either. That said, I’ll sure they would have don’t just as thorough a job.

[tanglewood]

Originally Posted by sailingharry

I want to be clear as I start this post that I am not trying to be argumentative. I understand the challenges ABYC faces when putting together a standard like this. And that for now at least, they lump all chemistries together. At least from my perspective, it doesn't bother me as I find the standard to be common sense and worthy of following.

As a thought experiment to investigate edge cases, imagine a totally unmanaged LFP bank. No balancing, no disconnects, no nothing. Four cells wired together and tossed into the battery compartment (religiously following E-11 and E-13 of course). The owner is somewhat observant and attentive, and keeps charging in something approaching the optimum operating zone. What is the most likely safety related potential failure? Fire? Some sort of off-gassing?

As I said, not trying to be argumentative. But these kinds of explorations can be insightful even for a well-built system that shouldn't approach those failure modes. Knowing the disaster your installation is trying to avert puts context on the work you are installing. As an example, understanding how fuses protect wires from fires makes it easy to understand that a fuse gets placed close to the battery on a battery cable, but not close to an alternator (rather, at the far end).

I think such a though exercise is exactly the way to approach stuff like this.


Speaking strictly for LFP, I'd be hard pressed to disagree with you. We all imagine different horror scenarios, and to me the worst is a rogue charger that just keeps charging the battery until it's roasted to a crisp. And in that situation I don't think it's any worse that similar run-away charging on a FLA or AGM bettery. In fact, it might be less dangerous because you don't have explosion risk and you aren't dumping sulfuric acid everywhere.

[Wandering]

Originally Posted by crayiii

I would be happy to provide my input on this. It’s about popcorn and movie time so I’ll give you a couple of thoughts.

First, hire someone like Ocean Planet to work with you on a design. They provide that service.

Have a separate charge and load bus

Have a backup power source for important loads.

Install an integrated system where everything communicates with each other.

Make sure you meet all your insurance companies requirements.

Obviously, that’s very high level.

You are assuming everybody uses lithium in an identical manner. This is not so. Those suggestions are very specific to one system.
How can you say those thing when some systems simply do not need full integration? My professional skipper buddies on very large superyachts all bemoan CANBUS.