[Rhodes22-list] A Different Approach to Adding Lithium Batteries To Your Boat

[Jesse Shumaker]

Thanks Peter.  That youtube channel has quite a bit of interesting
background.  I wonder if you have checked out https://atomvoyages.com/ or
the corresponding youtube channel
<https://www.youtube.com/user/atomvoyager/videos>.  There is lots of
interesting project work there.  I suspect a bunch of us on the list
probably watch a bunch of the same sailing you tube channels.  By the way,
thanks for posting the videos of your recent Maine trip.  It's always great
to watch your adventures.

An update from some of my posts of the electrical update I made over the
winter: the system that I ended up with was a the LiFePO4 as a house
battery charged by 30W solar panel mounted above the stern rail, and then a
small sealed lead acid battery on a separate circuit for my electric start
motor + motor lift.  The lead acid battery is changed by the two 10W solar
panels (that came with the R22) wired in series, as well as the
alternator.  So far this has worked out well.  Like a lot of my projects,
it's probably overkill.  Each of the batteries is under 30lbs so it is
easier to take them out for the off season.

Jesse Shumaker
S/V Zephyr

On Thu, Aug 11, 2022 at 2:52 PM Peter Nyberg <peter at sunnybeeches.com> wrote:

> There's been some interest in this topic in the past, and I recently
> stumbled upon a different take on the subject that I found interesting, and
> I thought I'd share.
>
> LiFePO4 batteries have some benefits that everyone at all interested is
> probably already aware of, but they also have some potential problems.  The
> biggest problems stem from the fact that the Battery Management System
> (BMS), may decide in some situations to take the battery offline.  If you
> are entirely dependent on the lithium batteries, this would leave you
> entirely without power.  In addition, if you were charging your lithium
> battery with an alternator at the time of disconnect, it is likely that the
> alternator would be ruined.
>
> There are complicated solutions to this problem involving additional
> equipment, but there's a guy who proposes the best approach is to just
> combine LiFePO4 and lead-acid batteries into a single battery bank.
>
> I won't bother trying to explain, because he does a pretty good job of it
> himself:
>
> https://www.youtube.com/watch?v=tAuPfgZgXec
>
> He's got a few more related videos on his YouTube channel, if you continue
> to be interested.
>
> --Peter
>
> P.S.  I'm not seriously considering doing this on my boat.
>
>