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Information about Zinc Carbon Battery



A Zinc-carbon dry cell or battery is packaged in a zinc can that serves as both a container and anode. It was developed from the wet Leclanché cell (IPA pronunciation: [lɛklɑːnˈʃei]). "Super" or "Heavy Duty" batteries, technically called zinc chloride cells, are an improved version from the cheaper "General Purpose" variety. The cathode is a mixture of manganese dioxide and carbon powder. The electrolyte is a paste of zinc chloride and ammonium chloride dissolved in water. Carbon-zinc batteries are the least expensive primary batteries and thus a popular choice by manufacturers when devices are sold with batteries included. They can be used in remote controls, flashlights, toys, or transistor radios, where the power drain is not too heavy.

A primary cell

A Zinc-carbon dry cell is described as a primary cell because as the cell is discharged, it is not intended to be recharged and must be discarded. "Battery Rejuvenators" were once marketed to restore partially discharged Zinc-carbon cells by applying a reverse current to them. However the effects of such devices were only temporary and prone to cause the cell to leak or burst. [https://www.medsun.net/participants/Uploads/100-110_BMIT3802.pdf] zinc-carbon cells are more likely to leak as they are soluble in water

Chemical Reactions

The container of the zinc-carbon dry cell is a zinc can. This contains a layer of NH4Cl with ZnCl2 aqueous paste separated by a paper layer from a mixture of powdered carbon & manganese (IV) oxide (MnO2) which is packed around a carbon rod.

Enlarge picture
Cross-section of a zinc-carbon battery.


In a dry cell, the outer zinc container is the anode (-). The zinc is oxidised according to the following half-equation.
Zn(s) → Zn2+(aq) + 2 e-
A graphite rod surrounded by a powder containing manganese(IV) oxide is the cathode(+). The manganese dioxide is mixed with carbon powder to increase the conductivity of the cathode mixture. The cathode reaction is as follows:

2MnO2(s) + 2 H+(aq) + 2 e- → Mn2O3(s) + H2O(l)


The H+ comes from the NH4+(aq):

NH4+(aq) + H2O(l) → H+(aq) + NH3(aq)


and the NH3 combines with the Zn2+.

In this half-reaction, the manganese is reduced from an oxidation state of (+4) to (+3).

There are other possible side-reactions, but the overall reaction in a zinc-carbon cell can be represented as:

Zn(s) + 2 MnO2(s) + 2 NH4+(aq) → Mn2O3(s) + Zn(NH3)22+(aq)


The battery has an e.m.f. of about 1.5 V. The approximate nature of the e.m.f is related to the complexity of the cathode reaction. The anode (zinc) reaction is comparatively simple with a known potential. Side reactions and depletion of the active chemicals increases the internal resistance of the battery, and this causes the e.m.f. to drop.

Leakage

When the dry cell has been used for a certain time, the zinc container becomes thinner because zinc metal is oxidised to zinc ions. Therefore Zinc Chloride Solution leaks out the battery. The old dry cell is not leakproof. It becomes very sticky as the paste leaks through the holes in the zinc case. The service life of the battery is short, with a shelf life of around 1.5 years.

Furthermore, the zinc casing in the dry cell gets thinner slowly, even when the cell is not being used. It is because the ammonium chloride inside the battery is acidic, reacting with the zinc.

The Zinc Chloride Cell

The (heavy duty) zinc chloride cell is an improvement on the original zinc-carbon cell, using purer chemicals and giving a longer life and steadier voltage output as it is used. Instead of an electrolyte mixture containing much NH4Cl, it is largely only ZnCl2 paste. The cathode reaction is thus a little different:

MnO2(s) + H2O(l) + e- → MnO(OH)(s) + OH-(aq)


as is the overall reaction:

Zn(s) + 2 MnO2(s) + ZnCl2(aq) + 2 H2O(l) → 2 MnO(OH)(s) + 2 Zn(OH)Cl(aq)

References

Eveready: Carbon Zinc Application Notes

Rayovac: Alkaline and Heavy Duty Application Notes

Power Stream Battery Chemistry FAQs
For the band, see .


A dry cell is a galvanic electrochemical cell with a pasty low-moisture electrolyte. A wet cell, on the other hand, is a cell with a liquid electrolyte, such as the lead-acid batteries in most cars.
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battery is a device consisting of one or more electrochemical cells, which store chemical energy and make it available in an electrical form. There are many types of electrochemical cells, including galvanic cells, electrolytic cells, fuel cells, flow cells, and voltaic cells.
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Zinc (IPA: /ˈzɪŋk/, from German: Zink) is a chemical element in the periodic table that has the symbol Zn and atomic number 30.
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Leclanché cell. It contained a conducting solution (electrolyte) of ammonium chloride, a cathode (positive terminal) of carbon, a depolarizer of manganese dioxide, and an anode (negative terminal) of zinc.
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International Phonetic Alphabet

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The International
Phonetic Alphabet
History
Nonstandard symbols
Extended IPA
Naming conventions
IPA for English The
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A cathode is an electrode through which (positive) electric current flows out of a polarized electrical device. Mnemonic: CCD (Cathode Current Departs). To dispel a common misconception, often incorrectly inferred from the correct fact that in all electrochemical
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Manganese(IV) oxide is the chemical compound MnO2, commonly called manganese dioxide. This blackish or brown solid occurs naturally as the mineral pyrolusite, which is the main ore of manganese. It is also present in manganese nodules.
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4, 2
(mildly acidic oxide)
Electronegativity 2.55 (Pauling scale)
Ionization energies
(more) 1st: 1086.5 kJmol−1
2nd: 2352.6 kJmol−1
3rd: 4620.5 kJmol−1

Atomic radius 70 pm
Atomic radius (calc.
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An electrolyte is a substance containing free ions that behaves as an electrically conductive medium. Because they generally consist of ions in solution, electrolytes are also known as ionic solutions, but molten electrolytes and solid electrolytes are also possible.
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Zinc chloride is the name of chemical compound with the formula ZnCl2 and its hydrates. Zinc chlorides, of which at nine crystalline forms are known, are colorless or white and highly soluble in water. ZnCl2 itself is hygroscopic and even deliquescent.
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Ammonium chloride (NH4Cl) (also Sal Ammoniac, salmiac, nushadir salt, zalmiak, sal armagnac, sal armoniac, salmiakki, salmiak and salt armoniack
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A primary cell is any kind of electrochemical cell in which the electrochemical reaction of interest is not reversible, so used in disposable batteries. The most common primary cells today are found in alkaline batteries; earlier carbon-zinc cells, with a carbon post as cathode and
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remote control is an electronic device used for the remote operation of a machine.

The term remote control can be also referred to as "remote" or "controller" when abbreviated.
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transistor radio is a small transistor-based radio receiver. Historically, the term "transistor radio" refers to a radio that is monoaural and typically receives only the 540–1600 kilocycle[1] AM broadcast band.
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For the band, see .


A dry cell is a galvanic electrochemical cell with a pasty low-moisture electrolyte. A wet cell, on the other hand, is a cell with a liquid electrolyte, such as the lead-acid batteries in most cars.
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A primary cell is any kind of electrochemical cell in which the electrochemical reaction of interest is not reversible, so used in disposable batteries. The most common primary cells today are found in alkaline batteries; earlier carbon-zinc cells, with a carbon post as cathode and
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Redox (shorthand for reduction/oxidation reaction) describes all chemical reactions in which atoms have their oxidation number (oxidation state) changed.

This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide, or the
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Conductivity may refer to:
  • Electrical conductivity, a measure of a material's ability to conduct an electric current
  • Thermal conductivity, the intensive property of a material that indicates its ability to conduct heat

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Redox (shorthand for reduction/oxidation reaction) describes all chemical reactions in which atoms have their oxidation number (oxidation state) changed.

This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide, or the
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In chemistry, the oxidation state is an indicator of the degree of oxidation of an atom in a chemical compound. The formal oxidation state is the hypothetical charge that an atom would have if all bonds to atoms of different elements were 100% ionic.
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Electromotive force (emf, ) is a term used to characterize electrical devices, such as voltaic cells, thermoelectric devices, electrical generators and transformers, and even resistors.
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volt (symbol: V) is the SI derived unit of electric potential difference or electromotive force.[1][2] It is named in honor of the Italian physicist Alessandro Volta (1745–1827), who invented the voltaic pile, the first modern chemical battery.
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The output impedance, source impedance, or internal impedance of an electronic device is the opposition exhibited by its output terminals to the flow of an alternating current (AC) of a particular frequency as a result of resistance, inductance and capacitance.
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Shelf life is that length of time that food, drink, medicine and other perishable items are given before they are considered unsuitable for sale or consumption. In some regions, a best before, use by or freshness date
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A year (from Old English gēr) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. By extension, this can be applied to any planet: for example, a "Martian year" is the time in which Mars completes its own orbit.
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