CN101937995A

CN101937995A - Zinc powder for alkaline manganese battery

Info

Publication number: CN101937995A
Application number: CN2010102687208A
Authority: CN
Inventors: 李建军
Original assignee: Jiangmen City Sanqi Battery Industry Co ltd
Current assignee: Jiangmen City Sanqi Battery Industry Co ltd
Priority date: 2010-08-30
Filing date: 2010-08-30
Publication date: 2011-01-05

Abstract

The invention discloses zinc powder for an alkali-manganese battery, which comprises 0.035-0.058 wt% of indium (In), 0.002-0.045 wt% of bismuth (Bi), 0.001-0.025 wt% of magnesium (Mg), 0.001-0.018 wt% of strontium (Sr) and mixed rare earth, the balance of zinc (Zn), 0.025-0.045 wt% of manganese (Mn) according to actual conditions, and 0.001-0.012 wt% of other improved trace elements such as aluminum, titanium, zirconium, calcium and the like, wherein the mixed rare earth comprises lanthanide rare earth metals such as lanthanum, cerium and the like. The zinc powder for the alkaline manganese battery, which meets the environmental protection requirement, has no mercury and cadmium and good battery performance, is formed by selecting non-toxic elements which do not cause pollution to the environment and replacing the existing commonly used mercury and cadmium.

Description

Zinc powder for alkaline manganese battery

The technical field is as follows:

the invention relates to the field of battery materials, in particular to zinc powder for an alkaline manganese battery, which replaces mercury and cadmium used in the production of the existing battery.

The background art comprises the following steps:

the zinc-manganese battery has the advantages of convenient and safe use and low price, is popular with consumers, is the battery which has the widest use and the largest output till now, and however, toxic substances such as mercury, cadmium and the like in the zinc-manganese battery material cause long-term pollution and harm to the living environment and the ecological environment of human beings.

With the increasing awareness of environmental protection, the battery industry has been forced to move toward green industrialization. China has formally stipulated that the production of batteries with mercury content higher than 0.0001% of the quality of the batteries is prohibited from 1/2005, and currently, the national environmental standard HJBZ009-1999 and the national standard GB/T7112-1998 of the batteries require that the mercury content of the batteries is less than or equal to 0.0001%, and the European Union 2006/66/EC also requires that the mercury content of the batteries is less than or equal to 0.0001%, so that the development of mercury-free batteries has profound significance to environmental protection.

Cadmium is harmful to the environment, seriously harms the renal function, the pulmonary function, the skeleton and the like of a human body, has the biological half-life period of 10-30 years in the human body, is a known toxic substance which is most easily accumulated in the human body, has the functions of carcinogenesis, teratogenesis and mutagenesis, does not have clear regulations and regulations in China to require cadmium-free zinc-manganese batteries, but European Union 2006/66/EC requires that cadmium is less than or equal to 0.002 percent, realizes cadmium-free zinc powder of the batteries, and has good social benefit and economic benefit.

The invention content is as follows:

the technical problem to be solved by the invention is to form the zinc powder for the alkaline manganese battery which meets the environmental protection requirement, has no mercury and cadmium and has good battery performance by selecting non-toxic elements which do not cause pollution to the environment and replacing the prior commonly used mercury and cadmium

The technical scheme adopted by the invention for solving the technical problems is as follows: the zinc powder for alkali-manganese cell contains 0.035-0.058 wt% of indium (In), 0.002-0.045 wt% of bismuth (Bi), 0.001-0.025 wt% of magnesium (Mg), 0.001-0.018 wt% of strontium (Sr) and mixed rare earth, and the rest is zinc (Zn).

In the zinc powder for the alkaline manganese cell, the zinc powder also contains 0.025-0.045 wt% of manganese (Mn). Manganese (Mn) is added as the case requires.

In the zinc powder for the alkaline manganese battery, the zinc powder also contains at least one of improved trace elements of aluminum, titanium, zirconium and calcium, and the content of the modified trace elements is 0.001 to 0.012 percent by weight.

In the zinc powder for the alkaline manganese cell, the mixed rare earth comprises the following rare earth elements in percentage by weight: lanthanum (La), cerium (Ce), gadolinium (Gd) and holmium (Ho) = 1: 0.5-1: 0.3-0.5: 0.5, and the content of the mixed rare earth is 0.05-0.55 percent of the weight of zinc.

The most adjacent element to cadmium is indium, the atomic radius of the indium is close to that of cadmium, the specific gravity of the indium is 7.3g/cm & lt 3 & gt and is close to that of zinc, 7.14g/cm & lt 3 & gt, the indium is easy to eutectic and not easy to produce specific gravity segregation, the indium has larger hydrogen overpotential, the generation of hydrogen is inhibited, namely, the zinc self-melting is slowed down, the surface affinity of the zinc is good, the contact resistance of the surface of a negative electrode can is reduced, and the cadmium can be replaced; bismuth can improve the hydrogen evolution potential and reduce the corrosion of a zinc electrode; magnesium also slows or inhibits the autolysis of the anode during long-term storage of the battery, alleviates the self-discharge effect of zinc, increases the mechanical strength of the negative can, and in addition, magnesium also increases the anode activity and improves the discharge performance of the battery.

The addition of lanthanide rare earth metals such as lanthanum and cerium to zinc powder can refine the macro and micro structure of zinc plate, improve the surface quality of negative electrode material, raise the corrosion rate to acid and alkali, increase the ductility and make it possess excellent cold and hot processing performance and low work hardening coefficient.

One or more of aluminum, titanium, zirconium, calcium and other elements are further added into the zinc powder to be mixed, so that the effect of comprehensive improvement can be achieved, for example, the ductility and the processability of titanium can be improved, the zirconium and the calcium can be refined, and the conductivity and the processability of aluminum can be improved.

In view of the influence of the corrosion rate, indium is the most effective element for reducing the corrosion rate, and the corrosion rate decreases as the amount of indium added increases, but from the viewpoint of the performance and cost, the above range is preferable: from the influence on the discharge performance, the addition of indium is beneficial to the discharge performance, the addition of magnesium improves the discharge performance, but the discharge performance is reduced if the addition amounts of indium and magnesium are too large, and the addition of rare earth metal and other improving elements also has certain influence on the discharge performance.

Compared with the prior art, the invention has the advantages that: 1. completely reaches the requirements of no mercury and cadmium, meets the requirement of environmental protection, and has 2, good discharge performance, strong corrosion resistance, large capacity of the prepared battery and good storage stability.

The specific implementation mode is as follows:

the present invention will be described in further detail with reference to examples

Example 1

Firstly, placing magnesium with high melting point at the bottom of a medium frequency induction furnace when melting is started, adding indium, bismuth, magnesium and mixed rare earth at the temperature of 500-650 ℃ after zinc ingots are completely melted, adding manganese according to the formula, alloying, fully stirring, heating the medium frequency induction furnace to 660-750 ℃, stopping heating, spraying and granulating the melted liquid under the action of high-pressure gas while the liquid is hot, immediately cooling the sprayed particles by using a coolant medium after leaving a nozzle, and heating, drying and screening the cooled particles to obtain the mercury-free and cadmium-free zinc powder.

The following zinc powder is prepared by the process:

the rare earth alloy comprises zinc (Zn), indium (In), bismuth (Bi), magnesium (Mg), strontium (Sr), manganese (Mn) and mixed rare earth, wherein the mixed rare earth consists of the following rare earth elements In percentage by weight: lanthanum (La), cerium (Ce), gadolinium (Gd), holmium (Ho) = 1: 0.75: 0.45: 0.5; the zinc powder comprises the following components In percentage by weight of zinc (Zn), indium (In), bismuth (Bi), magnesium (Mg), strontium (Sr), manganese (Mn) = 100: 0.038: 0.025: 0.018: 0.016: 0.038, and the zinc powder has the impurity mercury content of less than or equal to 0.0001 percent and the cadmium content of less than or equal to 0.002 percent

Example 2

In example 2, the process used was substantially the same as in example 1, except that the misch metal consisted of the following rare earth elements (by weight): lanthanum (La), cerium (Ce), gadolinium (Gd), holmium (Ho) = 1: 0.5: 0.3: 0.5; the weight percentages of the components of the zinc powder are zinc (Zn), indium (In), bismuth (Bi), magnesium (Mg), strontium (Sr), manganese (Mn) = 100: 0.035: 0.002: 0.001: 0.025, but the content of mercury impurities is less than or equal to 0.0001%, and the content of cadmium is less than or equal to 0.002%, which is the same as that In the embodiment 1.

Example 3

In example 3, the process used was substantially the same as in example 1, except that the misch metal consisted of the following rare earth elements (by weight): lanthanum (La), cerium (Ce), gadolinium (Gd), holmium (Ho) = 1: 0.5; the zinc powder comprises the components of zinc (Zn), indium (In), bismuth (Bi), magnesium (Mg), strontium (Sr), manganese (Mn) = 100: 0.058: 0.045: 0.025: 0.018: 0.045 In percentage by weight, but the content of mercury impurities is less than or equal to 0.0001%, the content of cadmium is less than or equal to 0.002%, and the weight percentage is the same as that of the zinc powder In the embodiment 1.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the technical solutions of the present invention in any way. Any simple modification, equivalent change and modification made to the above embodiments according to the technical spirit of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A zinc powder for an alkaline manganese battery is characterized in that: the zinc powder contains 0.035-0.058 wt% indium (In), 0.002-0.045 wt% bismuth (Bi), 0.001-0.025 wt% magnesium (Mg), 0.001-0.018 wt% strontium (Sr) and mixed rare earth, and the rest is zinc (Zn).

2. A zinc powder for an alkaline manganese cell according to claim 1, characterized in that: the zinc powder also contains 0.025-0.045 wt% of manganese (Mn).

3. A zinc powder for an alkaline manganese cell according to claim 2, characterized in that: the zinc powder also contains at least one of improved trace elements of aluminum, titanium, zirconium and calcium, and the content is 0.001 to 0.012 weight percent.

4. A zinc powder for an alkaline manganese cell according to claim 3, characterized in that: the mixed rare earth comprises the following rare earth elements in percentage by weight: lanthanum (La), cerium (Ce), gadolinium (Gd) and holmium (Ho) = 1: 0.5-1: 0.3-0.5: 0.5, and the content of the mixed rare earth is 0.05-0.55 percent of the weight of zinc.