Wire

[Talbot]

When I researched the best all round battery for use as the power for both thruster and 1000 w windlass. I was offered two real choices. One of these was a real specialist battery (= mega bucks) , the other was a carbon fibre reinforced wet battery, that could be used as a deep cycle battery, but was also suitable for engine start (500 cca iirc). Furthermore this battery would accept a faster charge rate than normal deep cycle and had a 5 year guarantee. - only downside was that it was twice as expensive as my standard cheapo leisure battery. (and a bit larger and heavier)

http://www.elecsol.com/html/vehiboat.html

[GordMay]

I’ll let Rick address technical niceties of battery design, merely noting that:
- Starting Batteries have Heavy Bus Bars
- Deep Cycle Batteries have Heavy Plates.
It seems reasonable that any true “Combination” battery would have both, and be more expensive than either.

[SG]

So?

I wouldn't put lead acid battery forward because i) I have AGM's already; and ii) I think it crazy to have a battery up there that sometimes get challenged by things that happen at the pointy end of a sailboat in a tough seaway.

So, having said that:

IS the installation of a smaller, lighter installation of a 40# battery and some smaller, less expensive wire to and from better than running hundreds of dollars and alot heavier wire forward and back? (Not to mention the hassles of trying to snake cables the size of your little finger through the boat from the stern.)

Most of us don't expect to need to use the windlass more often than every two hours.

(I guess, it also begs the question: if weight isn't an issue, then should you mount a starting battery up there anyway -- even if you have a 4/0 or 2/0 cable running back and forth just to avoid hassles with the the voltage drop? [I've hesitated because i) I have the big cable going up and back already, and ii) I'm concerned with the fuse protections.]

[Andina Marie]

The big advantage of a forward battery is avoiding the cost and running the cables as you describe. If they are already there and of adequate gauge I don't see any advantage in installing a winch battery forward.

[Rick]

O.K. I need Sean's discression and tact here: the article mentioned by Andina regarding "short cycling..." is prefaced by the admission that the author has no technical expertise to make such statements with credibility. Again, no offense, but the whole article contains false information.

I say, again, there is NO factual basis for the myth that lead-acid batteries exhibit so-called "memory" which can be removed by discharging and then recharging. AGAIN, the belief of this myth is based upon the fact that any loss of capacity can often be ameloriated to some degree by RECHARGING the battery. The REAL basis of the myth is that the battery must be DISCHARGED to some (or any) degree in order to do this. If you look at the preface to the article the author ADMITS that there is no technical basis for his submission.

ONE FACT: Any discharge of a lead-acid battery decreases the lifetime of the battery. Why add to the lifetime problem by purposefully discharging the battery without gleaning some use from it?

Another fact: Application of a voltage sufficient to repleat self-discharge or minimal sulphation requires more than what was available to boating consumers in chargers before 1984 or so. In fact, proper chargers were not "accepted" by consumers until the late nineties and those were largely from Heart Interface and Trace Engineering as well as Ample Power. NO large company provided such solution.

Historically it was Dave Smead and Rick Proctor who beat the drum regarding proper charging techniques based upon lead-acid text books written by true experts recognized by industrial users so that people in this miniscule boating market (relatively speaking) could benefit from the electochemistry which the storage battery military and industrial markets applied.

So-called "memory" effects of lead-acid batteries have never been documented by the electrochemists who "wrote the books" as well as other applicable literature. In no case have I read of any benefit from discharging a lead-acid battery in orderi to regain any attributes related to available stored energy.

Again, I must stress that APPARENT recovery of stored energy attributes due to discharging is ONLY due to the CHARGING function. What is NOT apparent to the casual user of lead-acid batteries is that they have never made scientific proofs which separate discharge phenomenon from charge phenomenon versus all of the other electrochemical variables. The electrochemists HAVE and, guess what? The results have not changed since some of the original publications by George Wood Vinal: "Storage Batteries" (A General Treatise On the Physics and Chemistry of Secondary BAtteries and Their Engineering Applications) published in 1924. Other editions came later and sustained the author's status in the field to this day. There are other well aclaimed authors as well stating later similar results.

There is more myth regarding the appication (and misapplication) of lead-acid batteries in the cruising community than anywhere else that I have been able to observe in decades of engineering design and application of my "career".

I hope that some of these threads lead to illumination and benefit of you "out there" using lead-acid batteries. It is pointless for authors writhing articles in the boating world to keep refering to other author's articles which refer to other articles NONE of which have a basis in the science and technology of the literature recognized by the rest of the scientific world. Here I do so hopefully in a manner which somehow relates to the casual non-technical reader without radically degrading the true technical basis of my statements.

[irwinsailor]

Well. I ordered Anchor 4/0 tinned wire from Defender. The price was $2.09 a foot. I very good price for the wire from what I can see. It is less money than the welding cable that I was thinking about buying when I first posted the question about wire. Thank you everyone for your help.