Editing Zinc (section)

===Anti-corrosion and batteries===
[[File:Feuerverzinkte Oberfläche.jpg|thumb|Hot-dip handrail [[galvanization|galvanized]] crystalline surface|alt=Merged elongated crystals of various shades of gray.]]
[[File:Zinkanode neu.jpg|thumb|Zinc [[sacrificial anode]]]]
Zinc is most commonly used as an anti-[[corrosion]] agent,<ref name="Greenwood1997p1203">{{harvnb|Greenwood|Earnshaw|1997|p=1203}}</ref> and galvanization (coating of [[iron]] or [[steel]]) is the most familiar form. In 2009 in the United States, 55% or 893,000 tons of the zinc metal was used for galvanization.<ref name="USGS-yb2006">{{cite web |date=February 2010 |url=http://minerals.usgs.gov/minerals/pubs/commodity/zinc/myb1-2009-zinc.pdf|access-date=June 6, 2001 |title=Zinc: World Mine Production (zinc content of concentrate) by Country |work=2009 Minerals Yearbook: Zinc |publisher=United States Geological Survey |location=Washington, D.C. |url-status=live|archive-url=https://web.archive.org/web/20110608154555/http://minerals.usgs.gov/minerals/pubs/commodity/zinc/myb1-2009-zinc.pdf|archive-date=June 8, 2011}}</ref>

Zinc is more reactive than iron or steel and thus will attract almost all local oxidation until it completely corrodes away.<ref name="Stwertka1998p99">{{harvnb|Stwertka|1998|p=99}}</ref> A protective surface layer of oxide and carbonate ({{chem|Zn|5|(OH)|6|(CO|3|)|2|)}} forms as the zinc corrodes.<ref name="Lehto1968p829">{{harvnb|Lehto|1968|p=829}}</ref> This protection lasts even after the zinc layer is scratched but degrades through time as the zinc corrodes away.<ref name="Lehto1968p829" /> The zinc is applied electrochemically or as molten zinc by [[hot-dip galvanizing]] or spraying. Galvanization is used on chain-link fencing, guard rails, suspension bridges, lightposts, metal roofs, heat exchangers, and car bodies.<ref name="Emsley2001p503">{{harvnb|Emsley|2001|p=503}}</ref>

The relative reactivity of zinc and its ability to attract oxidation to itself makes it an efficient [[sacrificial anode]] in [[cathodic protection]] (CP). For example, cathodic protection of a buried pipeline can be achieved by connecting anodes made from zinc to the pipe.<ref name="Lehto1968p829" /> Zinc acts as the [[anode]] (negative terminus) by slowly corroding away as it passes electric current to the steel pipeline.<ref name="Lehto1968p829" />{{efn|Electric current will naturally flow between zinc and steel but in some circumstances inert anodes are used with an external DC source.}} Zinc is also used to cathodically protect metals that are exposed to sea water.<ref>{{Cite journal|title=A comparative study of the electrochemical behaviour of Algerian zinc and a zinc from a commercial sacrificial anode|last=Bounoughaz|first=M.|author2=Salhi, E.|author3=Benzine, K.|author4=Ghali E.|author5=Dalard F.|journal=Journal of Materials Science|volume =38|issue=6|pages=1139–1145|doi=10.1023/A:1022824813564|date=2003|bibcode = 2003JMatS..38.1139B |s2cid=135744939}}</ref> A zinc disc attached to a ship's iron rudder will slowly corrode while the rudder stays intact.<ref name="Stwertka1998p99" /> Similarly, a zinc plug attached to a propeller or the metal protective guard for the keel of the ship provides temporary protection.

With a [[standard electrode potential]] (SEP) of −0.76 [[volt]]s, zinc is used as an anode material for batteries. (More reactive lithium (SEP −3.04 V) is used for anodes in [[Lithium battery|lithium batteries]] ). Powdered zinc is used in this way in [[alkaline battery|alkaline batteries]] and the case (which also serves as the anode) of [[Zinc–carbon battery|zinc–carbon batteries]] is formed from sheet zinc.<ref>{{Cite book|first=Jürgen O.|last=Besenhard|title=Handbook of Battery Materials|publisher=Wiley-VCH|isbn=978-3-527-29469-5|date=1999|bibcode=1999hbm..book.....B}}</ref><ref>{{Cite journal|doi=10.1016/0378-7753(95)02242-2|date=1995|title=Recycling zinc batteries: an economical challenge in consumer waste management|first=J.-P.|last=Wiaux|author2=Waefler, J. -P. |journal=Journal of Power Sources|volume=57|issue=1–2|pages=61–65|bibcode = 1995JPS....57...61W }}</ref> Zinc is used as the anode or fuel of the [[zinc–air battery]]/fuel cell.<ref>{{Cite book|chapter=A design guide for rechargeable zinc–air battery technology|last=Culter|first=T.|doi=10.1109/SOUTHC.1996.535134|title=Southcon/96. Conference Record|isbn=978-0-7803-3268-3|date=1996|page=616|s2cid=106826667}}</ref><ref>{{cite web|url=http://www.electric-fuel.com/evtech/papers/paper11-1-98.pdf |title=Zinc Air Battery-Battery Hybrid for Powering Electric Scooters and Electric Buses |first=Jonathan |last=Whartman |author2=Brown, Ian |publisher=The 15th International Electric Vehicle Symposium |access-date=October 8, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20060312003601/http://www.electric-fuel.com/evtech/papers/paper11-1-98.pdf |archive-date=March 12, 2006 }}</ref><ref>{{cite journal|title=A refuelable zinc/air battery for fleet electric vehicle propulsion|journal=NASA Sti/Recon Technical Report N|volume=96|pages=11394|last=Cooper|first=J. F.|author2=Fleming, D.|author3=Hargrove, D.|author4=Koopman, R.|author5=Peterman, K|publisher=Society of Automotive Engineers future transportation technology conference and exposition|osti = 82465|bibcode=1995STIN...9611394C|year=1995}}</ref> The [[Zinc–cerium battery|zinc-cerium]] [[redox flow battery]] also relies on a zinc-based negative half-cell.<ref name="Xie1">{{cite journal|last1=Xie|first1=Z.|last2=Liu|first2=Q.|last3=Chang|first3=Z.|last4=Zhang|first4=X.|title=The developments and challenges of cerium half-cell in zinc–cerium redox flow battery for energy storage|journal=Electrochimica Acta|date=2013|volume=90|pages=695–704|doi=10.1016/j.electacta.2012.12.066}}</ref>