I Built a 45' cat, sailed a bit, Now What?

[jeepers]

Hundreds of volts gives me the willies on water, but for no really good reason. (More deaths occur from contact with 120 v than 440 v, and 120 v is common on boats.) One should observe loads of safety precautions when working with such things... but it would be a fun project!

Good luck![/QUOTE]

You need to be afraid, Very afraid
Takes 2 amps to kill you.But you can handle 10,000's of volts with little current
There have been a few deaths with people playing with Electric car batteries.
AC voltage . The alternating type will blow you off maybe hand & fingers too. DC voltage Not so lucky. Remember your Biology Labs...the battery leads to the frogs leg muscle. DC locks you on by contracting all the muscles>NO release until no power or YOU burn through.
Those batteries have inter module/bank disconnects. Wonder why?

[Ken Fry]

Originally Posted by jeepers

I have done some research/investigation into this.
The Leaf & similar batteries are air cooled.
They give off huge amounts of heat which is usually the reason for failure in the middle battery sections which would suppose ventilation inadequate.
A boat pontoon hull is not well ventilated.
Chevrolet Volt is water cooled.

You can pull drive motors from one brand batteries from another & so on.
The batteries are made up of sections so voltage applied is easily assembled

An advantage of the Leaf is that a single car yields twice the battery pack size. There is an advantage to buying a whole car, because a totalled car has a lower value than its parted-out value. So you'd need two Volts to equal one leaf. But your point is a good one: depending on usage pattern, water cooling can be a good thing.

In driving around in my little plug-in hybrid, the cells (passive air cooling) stayed cool enough even though I could drain them in an hour (at an average 40 mph). In a boat, with the same small pack, I might want four hours or six hour range, meaning much lower draw and much lower temperature. In my particular boat, (which has the old pack from my hybrid) that would mean something like 10 miles range, which is fine for my needs (an evening dinner cruise, etc.) If I want to actually go somewhere, I'll sail. (Or if I need to go somewhere fast, fire up the ICE). But in any case the temperature depends upon the usage, and even non forced air can work, in the right condition.

[Ken Fry]

Originally Posted by jeepers

You need to be afraid, Very afraid
Takes 2 amps to kill you.But you can handle 10,000's of volts with little current
There have been a few deaths with people playing with Electric car batteries.
AC voltage . The alternating type will blow you off maybe hand & fingers too. DC voltage Not so lucky. Remember your Biology Labs...the battery leads to the frogs leg muscle. DC locks you on by contracting all the muscles>NO release until no power or YOU burn through.
Those batteries have inter module/bank disconnects. Wonder why?

Funny -- I did exactly that frog thing as a science fair project... about 60 years ago!

And yes, the tales in the electric car enthusiast building world are scary. I've taught some electrical safety courses to industrial workers, so have heard many frightening tales: people getting blown out of switchgear rooms from arc blast, for instance. But even seemingly innocuous 12 volt car batteries have exploded when someone drops a wrench across the terminals.

Fun with sparks!

[jeepers]

https://www.youtube.com/watch?v=JHUQiRyVV3Y

For Information without opinion

Not sure if anyone posted this ..
But Sailing Uma is an all electric boat..

[Cadence]

Originally Posted by Ken Fry

Funny -- I did exactly that frog thing as a science fair project... about 60 years ago!

And yes, the tales in the electric car enthusiast building world are scary. I've taught some electrical safety courses to industrial workers, so have heard many frightening tales: people getting blown out of switchgear rooms from arc blast, for instance. But even seemingly innocuous 12 volt car batteries have exploded when someone drops a wrench across the terminals.

Fun with sparks!

One thing I hadn't seen mentioned. AC will release you, get across higher DC voltages and you are toast.