calcium battery

Hi; Has anybody any knowledge of the calcium batteries that are now available for vehicles. How does their construction stand up to 4X4 and marine use ? What are the advantages against the old lead acid types. Thanks for any enlightenment. Frank

Reply to
thesnowbaron
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The calcium is added to make the lead plates stronger. The downside is that they require more frequent water additions.

Reply to
Gene S. Snider

in article snipped-for-privacy@4ax.com, Gene S. Snider at snipped-for-privacy@insightbbspam.com wrote on 11/28/03 1:38 PM:

My impression is that he was talking about calcium as if it were an electrode rather than an alloying element. If lithium can be used as a battery anode, why not calcium?

To go on with a follow-up question: Does the presence if calcium in lead reduce the time a (calcium) lead-acid battery can hold its charge? Thinking by analogy, if copper or another metal present in zinc can produce local currents that corrode the zinc, why would that not happen with calcium in a lead anode?

Bill

Reply to
Repeating Decimal

Because calcium is not a metal. Corrosion occurs with at least two metals in an electrolyte.

Dave M.

Reply to
Dave M.

I have worked with many battery technologies, and have never seen calcium used other than as a enhancement for a lead-acid battery.

Could it be that the OP was confused and meant a Sodium Sulfur battery?

Reply to
Guy Macon

1) Calcium IS a metal (a so-called "light" metal).

2) in your "standard" lead/acid battery at least one of the two "active" electrodes is a compound containing lead. But for a low tech lead/acid cell, you can start with two sheets of pure lead in H2SO4 and start charging.

Reply to
John Gilmer

Early lead-acid battery designs experimented with a variety of allows to strengthen the plates. The positive plate, made from PbO is very brittle material and prone to shattering under the slightest vibration. Early designs commonly used a lead-antimony alloy 'grid' into which the lead oxide paste is formed.. These types of batteries 'used' a lot of water and had removable vent-caps to allow adding more water as needed. A newer design (now 'standard' in automobiles) is the lead-calcium grid.

Lead-calcium have much lower standby losses and can retain their charge for a longer time than lead-antimony. They also use less water. With a larger volume built into the battery above the plates, these batteries can go for years without needing water. The so-called 'maintenance-free' battery with non-removable vent-caps is a lead-calcium design.

But they have a drawback. If they are deep-cycled (deeply discharged) several times, there life is very short. A lead-calcium can be fully discharged only 80 to 200 times before the battery is pretty much crap. The lead-antimony designs, although they use more water, and self-discharge faster, can handle 1500 to 2000 such cycles.

For automotive, engine starting is just a short discharge of less than 20% of total capacity, so the maintenance-free lead-calcium is the clear winner. But for golf-carts, fork-lifts, PV installations, or anywhere you need deep-cycling, lead-antimony have advantages (but require more maintenance).

daestrom

P.S. They do make a pure lead grid design, with very good standby characturistics, but it doesn't last long in vibration-prone environments.

Reply to
daestrom

Wasn't there also batteries for Autos that used molten calcium which had very high energy per unit weight purposed. The problem was that before the battery could be used, the calcium had to be heated to the molten state as I remember it. . . I DO NOT FOLLOW MANY OF THESE NEWS GROUPS To answere me address mail to snipped-for-privacy@aol.com

Reply to
BUSHBADEE

in article XPUxb.1467$ snipped-for-privacy@news02.roc.ny, Dave M. at snipped-for-privacy@frontiernet.net wrote on 11/28/03 7:58 PM:

On what planet is calcium not a metal? It need not be a metal, but it certainly can be.

Bill

Reply to
Repeating Decimal

No. No such battery ever existed.

You are thinking of the Sodium-Sulfur battery used in the (1992?) Ford Ecostar van. I believe that they made 68 of them.

That battery had a solid electrolyte consisting of beta-aluminum ceramic and liquid electrodes consisting of molten sulfur and sodium at 325 degrees C.

See

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I used just such a battery to power the guidance system for a solid fuel booster rocket. The heat of the booster melted the Sodium and Sulfur.

No.

Why you shouldn't ask for E-mail responses on Usenet:

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Why "Reply by email, I don't read this newsgroup" gets flamed:
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The Basic Rules of Netiquette (search for "E-Mail Me"):
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Reply to
Guy Macon

Elemental calcium certainly *is* a metal.

Reply to
Keith R. Williams

You can imagine how embarrased I am. :-(

Reply to
Dave M.

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