CN105609784A

CN105609784A - Method for preparing lead-acid storage battery positive grid from praseodymium-cerium doped lead calcium tin aluminum alloy

Info

Publication number: CN105609784A
Application number: CN201510589054.0A
Authority: CN
Inventors: 刁国旺; 朱守圃; 陈曼玉; 吴甜; 瞿姗姗; 王世双
Original assignee: Yangzhou University
Current assignee: Yangzhou University
Priority date: 2015-09-16
Filing date: 2015-09-16
Publication date: 2016-05-25

Abstract

The invention relates to a method for preparing a lead-acid storage battery positive grid from a praseodymium-cerium doped lead calcium tin aluminum alloy, and belongs to the fields of material production technology and scientific research technology. The method comprises the following steps: firstly clipping the lead calcium tin aluminum alloy into small blocks to be mixed with rare earths such as Pr and Ce in a quartz boat, and carrying out calcination in an inert atmosphere so as to form the uniform praseodymium-cerium doped lead calcium tin aluminum alloy; then putting the praseodymium-cerium doped lead calcium tin aluminum alloy in a mold for injection molding, then applying epoxy resin, and performing polishing after solidification. According to the method, the rare earths such as Pr and Ce are added into the lead calcium tin aluminum alloy for the positive grid, so that the oxygen evolution potential is moved positively by about 0.12 V. This shows that the rare earths such as Pr and Ce achieve an obvious effect of inhibiting oxygen evolution of the lead calcium tin aluminum alloy, and the performance of a lead-acid storage battery is further improved preferably.

Description

Praseodymium cerium doping Pb-Ca-Sn-Al alloy is prepared the method for process for positive slab lattice of lead-acid accumulator

Technical field

The invention belongs to production technology and the scientific research field of manufacture of materials technology and scientific research technical field, particularly lead-acid accumulator.

Background technology

Have the characteristics such as cheap, safe, high rate charge-discharge due to lead-acid accumulator, it has obtained in fields such as electric bicycle, back-up source, startup power supplys using widely. Further promoting its performance is the direction that lead-acid accumulator industry is constantly pursued.

Grid has played very important effect in lead-acid accumulator. Although the charging current of the both positive and negative polarity of lead-acid accumulator is reciprocity. But anode plate grid is thick more a lot of than negative electrode grid in the actual generation of lead-acid accumulator, this is mainly because anode plate grid can corrode in charge and discharge process. The basic reason of anode plate grid corrosion is in the time of be greater than-0.3V of electrode electromotive force, lead and metal are in thermodynamic instability state, and in fact the current potential of positive plate will be for a long time on this numerical value, particularly in charging process, the easier betatopic of lead and alloy thereof. Therefore, in anode plate grid, the Pb in lead-containing alloy will change PbSO in aqueous sulfuric acid₄, and be further converted to PbO₂, this will cause the corrosion of anode plate grid.

But the side reaction of analysing oxygen of anode plate grid is also very important in the time of charging, water betatopic has generated oxygen, and oxygen reacts generation lead oxide after moving to negative pole with lead, and lead oxide has further generated lead sulfate with acid reaction. Be not difficult to find out, the side reaction of anodal oxygen uptake reaction, is converted into the lead sulfate that replaces equivalent electronics to participate in the reaction of brown lead oxide, and this will cause anodal lead sulfate residue, and this process has also consumed part water, this is totally unfavorable for analysing valve control type lead-acid accumulator battery.

Lead-calcium alloy has good characteristic, has been widely used in slab lattice alloy of lead-acid battery. Research shows, some trace elements is added to the generation that wherein can effectively reduce side reaction.

Summary of the invention

The object of the invention is to propose the rare-earth metal doped Pr of a kind of Pb-Ca-Sn-Al alloy, and prepare a kind of preparation method of the positive grid alloy with oxygen evolution potential.

The present invention includes following steps:

1) Pb-Ca-Sn-Al alloy is cut into fritter and rare earth Pr and Ce and is blended in quartz boat, in inert atmosphere, calcine, form the praseodymium cerium doping Pb-Ca-Sn-Al alloy of homogeneous;

2) praseodymium cerium doping Pb-Ca-Sn-Al alloy is placed in to mould injection mo(u)lding, then applies epoxy resin, polishing after solidifying.

The present invention by anode plate grid with adding rare earth element Pr and Ce in Pb-Ca-Sn-Al alloy, to further improving overpotential for oxygen evolution. In inert atmosphere, calcining, is the oxidation for fear of each element in alloy. Found through experiments and add a certain proportion of mishmetal Pr and Ce in Pb-Ca-Sn-Al alloy, make its oxygen evolution potential about 0.12V that shuffled. This shows that rare earth element Pr and Ce have played obvious inhibition Pb-Ca-Sn-Al alloy and analysed the effect of oxygen. This will contribute to further to promote the performance of lead-acid accumulator.

In the present invention, the injection mo(u)lding of alloy is to study for alloy more easily, applies epoxy resin and is in order to make electrode retain identical contact area with electrolyte when the test, and this is relatively very important for oxygen evolution potential size.

Calcium in lead calcium tin aluminium content 0.07～0.10% of the present invention, tin content 0.6～1.2%, aluminium content 0.01～0.04%. Wherein lead-calcium alloy has the characteristic such as good corrosion resistance, life-span length, and tin can strengthen charging current, and aluminium can be protected calcium and play the effect of nucleator.

Described Rare-Earth Ce is 0.01～0.1: 100 with the mixing quality ratio of Pb-Ca-Sn-Al alloy. This experiment has proved to play the effect that improves overpotential for oxygen evolution adding of a small amount of Rare-Earth Ce, makes production cost less simultaneously.

Rare earth Pr of the present invention is 0.01～0.1: 100 with the mixing quality ratio of Pb-Ca-Sn-Al alloy. This experiment has proved to replace part Rare-Earth Ce can further improve overpotential for oxygen evolution with rare earth Pr.

Described calcining heat condition is 1000～1200 DEG C, and calcination time is 20～50min, adopts quartz pushrod to stir in calcination process 2～5 times. This calcining heat can ensure the fusing of rare earth Pr and Ce, is beneficial to the alloy that forms homogeneous with plumbous calcium tin aluminium.

Described polishing is polished to epoxy resin bottom surface. All the oxides in order further to remove electrode surface to the polishing of electrode bottom surface and pre-polarization, to study more accurately the performance of alloy.

Concrete polishing is first to use aluminum oxide sandpaper, then polishes with abrasive paper for metallograph. Concrete polishing is first to polish with the larger aluminum oxide sandpaper of granularity, fast the bottom surface of electrode is polished, then polishes with the less abrasive paper for metallograph of granularity, so that bottom surface is further polished smooth.

Brief description of the drawings

Fig. 1 is the resistant to elevated temperatures alundum tube in the inventive method adheres to formation on glass mould by epoxy resin.

Fig. 2 is the electrode that the inventive method is made.

Fig. 3 is Pb-Ca-Sn-Al alloy electrode and the linear sweep voltammetry curve map that adds the Pb-Ca-Sn-Al alloy electrode of 0.05% rare earth Pr, Ce.

Detailed description of the invention

One, the plumbous calcium tin aluminium doping of preparation preparation praseodymium cerium alloy:

1. weighing, pre-treatment

Alloy grid is drawn materials from the calcium in lead calcium tin aluminium content 0.07～0.10% of storage battery factory's routine use, tin content 0.6～1.2%, aluminium content 0.01～0.04%. Pb-Ca-Sn-Al alloy polished and be cut into fritter, then accurately weighing 20～30g. Polishing is by the oxide removal of alloy surface.

The amount that takes rare earth Pr is 0.025% of Pb-Ca-Sn-Al alloy quality, and the amount that takes Rare-Earth Ce is 0.025% of Pb-Ca-Sn-Al alloy quality.

2. the preparation of alloy:

The Pb-Ca-Sn-Al alloy of weighing is placed in to quartz boat, then to the rare earth Pr and the Rare-Earth Ce that add weighing in quartz boat, then quartz boat is put into tube furnace.

By oil pump, the gas in tube furnace is extracted out, and then pass into argon gas or nitrogen, circulate after 3～4 times, in argon gas or nitrogen atmosphere, be warming up to 1000 DEG C with the heating rate of 5 DEG C/min, after heating 15～30min, after stirring with quartz pushrod, continuation heating 20～50min obtains the alloy of homogeneous.

Two, the preparation of electrode:

Make in advance mould:

Mold materials a: internal diameter is the alundum tube that 0.8cm, external diameter are 1.2cm; Epoxy resin; A slice plate glass.

By epoxy resin, one end of alundum tube is bonded on a large face of plate glass.

In the mould making, stretch into the copper cash that a diameter is 1.0mm, and make more than one end of copper cash is positioned at the upper port of alundum tube, as shown in Figure 1.

The alloy that mixes homogeneous is taken out rapidly and poured in the alundum tube of mould, injection mo(u)lding. After cooling, by the method that applies epoxy resin, the side of electrode is applied, more than placing 24h at normal temperatures, make epoxy resin completely curing.

First use aluminum oxide sandpaper, then the bottom polishing light to Fig. 2 electrode with abrasive paper for metallograph, makes electrode again.

Three, the test of electrode:

The test of electrode is carried out with three-electrode system, and taking the electrode prepared as working electrode, saturated calomel electrode is reference electrode, and platinum electrode is to electrode, and the sulfuric acid of 1.28g/mL is electrolyte. First electrode is polarized to remove its surperficial oxide at 1.19V, then by linear sweep voltammetry, the electrode of preparation is carried out to the investigation of oxygen evolution potential, the speed of sweeping of electrode is 5mV/s, and potential range is 1.5～2.7V, to investigate the size of oxygen evolution potential.

Meanwhile, according to undope preparation and the test of electrode of Pr and Ce of same step, add rare earth Pr and Ce impact with plumbous calcium tin aluminium grid alloy oxygen evolution potential on positive pole to contrast;

Four, performance characterization:

Fig. 3 is for to show: the Pb-Ca-Sn-Al alloy electrode that the oxygen evolution potential that adds the Pb-Ca-Sn-Al alloy electrode of the Rare-Earth Ce of 0.025% rare earth Pr and 0.025% does not add rare earth Pr and the Ce about 0.12V that shuffled. This shows that compound rare-earth Pr and Se have good inhibitory action to the oxygen of analysing of Pb-Ca-Sn-Al alloy.

Claims

1. praseodymium cerium doping Pb-Ca-Sn-Al alloy is prepared the method for process for positive slab lattice of lead-acid accumulator, it is characterized in that comprising the steps:

2. method according to claim 1, is characterized in that described calcium in lead calcium tin aluminium content 0.07～0.10%, tin content 0.6～1.2%, aluminium content 0.01～0.04%.

3. according to method described in claim 1 or 2, it is characterized in that described rare earth Pr and the mixing quality ratio of Pb-Ca-Sn-Al alloy are 0.01～0.1: 100.

4. according to method described in claim 1 or 2, it is characterized in that described Rare-Earth Ce and the mixing quality ratio of Pb-Ca-Sn-Al alloy are 0.01～0.1: 100.

5. method according to claim 1, is characterized in that described calcining carries out in tube furnace, and described inert atmosphere is argon gas or nitrogen.

6. method according to claim 5, is characterized in that described calcining heat condition is 1000～1200 DEG C, and calcination time is 20～50min, adopts quartz pushrod to stir in calcination process 2～5 times.

7. method according to claim 1, is characterized in that described polishing polishes to epoxy resin bottom surface.

8. method according to claim 7, first uses aluminum oxide sandpaper while it is characterized in that described polishing, then polish with abrasive paper for metallograph.