Battery containing antimony

In some cases, the electrode reaches some potential value at which an electrochemical dissolution of its components into the electrolyte occurs for example, the positive grid of lead-acid batteries contains antimony at the high potential of the grid, Sb can be oxidized to soluble SbO which can be reduced at the negative lead electrode. An antimony deposit then occurs leading to an acceleration of the self-discharge corrosion reaction. 

Reverberator Furnace. Using a reverberatory furnace, a fine particle feed can be used, the antimony content can be controlled, and batch operations can be carried out when the supply of scrap material is limited. However, the antimony-rich slags formed must be reduced in a blast furnace to recover the contained antimony and lead. For treating battery scrap, the reverberatory furnace serves as a large melting faciUty where the metallic components are hquefted and the oxides and sulfate in the filler material are concurrently reduced to lead metal and the antimony is oxidized. The furnace products are antimony-rich (5 to 9%) slag and low antimony (less than 1%) lead. 

The element antimony is used to harden lead for use in lead-acid storage batteries. One of the principal antimony ores is stibnite, which contains antimony in the form of Sb2S3. Antimony is obtained through the reduction that occurs (from the +3 oxidation state to the zero oxidation state of pure antimony) when Sb2S3 reacts with the iron in iron scrap. Wliat is the mass of antimony in 14.78 lb of Sb2S3 ... 

The grids of both flat-plate and tubular batteries should not contain antimony or any other additive that may decrease the hydrogen overpotential of the negative electrode. Indeed, it is recommended that ultra-pure lead be used to manufacture both the grids and the active material in order to avoid the possibility of excessive self-discharge at either the positive or the negative plates. 

The grid metallics should be stored and recovered separately from the battery paste so that metals from the alloys in the battery grids do not contaminate the relatively pure lead paste, which is ideal for producing soft lead. Alloys used to manufacture VRLA batteries do not contain either antimony or arsenic, and this means that the potential hazard of stibine (antimony hydride, SbHs) and arsine (arsenic hydride, AsHs) formation during the storage of the metallics is removed. Many automotive batteries with antimonial and arsenical alloys are still in use. 

The performance of wet batteries degrades with long periods of inactivity, especially when stored at warm temperatures. A loss of 1 to 3% of capacity each day is possible with SLI batteries that contain antimonial lead grids. The loss on stand can be much lower for maintenance-free batteries (0.1 to 3%/day). When lead-acid batteries must be stored for a long time, especially in high ambient temperatures, or when batteries are shipped for export, their performance can be stabilized by removal of the electrolyte by one of several methods. 

Lead is worked and used in both unalloyed and alloyed form. Hard lead e.g. contains antimony and is used in batteries. 

Surprisingly the water consumption of a starter battery, provided that it contains antimonial alloys, is affected by the separator. Some cellulosic separators as well... 

The "lead storage battery contains a trace of arsenic along with 3% antimony. Lead shot, which are formed by allowing drops of molten lead to fall through the air, contains from 0,5 to 2,0% arsenic. The presence of arsenic raises the surface tension of the liquid and hence makes the shot more spherical,... 

In Figure 18.18, results of floating tests on stationary batteries with selenium alloys are compared with tests published by the Swiss Post Office in 1976. For his well founded experiments, Gerber used industrial batteries supplied by several manufacturers. The grid material of these batteries contained about 10% antimony. Some results on stationary batteries equipped with lead—calcium alloys are also given in Figure 18.18. 

The lead-bearing components ate released from the case and other nordead-containing parts, followed by the smelting of the battery plates, and refinement to pure lead or specification alloys. The trend toward battery grid alloys having Httle or no antimony, increases the abiHty of a recovery process to produce soft lead (refined). As requited in the production of primary lead, each step in the secondary operations must meet the environmental standards for lead concentration in ait (see Air pollution Lead compounds, industrial toxicology). 

Automobile battery grids employ about 1—3 wt % antimony—lead alloys. Hybrid batteries use low (1.6—2.5 wt %) alloys for the positive grids and nonantimony alloys for the negative grids to give reduced or no water loss. The posts and straps of virtually all lead—acid batteries are made of alloys containing about 3 wt % antimony. 

Fig. 4. Grain structure of lead—2 wt % antimony alloy battery grid at a magnification of 50x (a) no nucleants (b) containing 0.025 wt % selenium as a grain...

Low (2—5 wt %) antimony, low (2—5 wt %) tin lead alloys are used for automobde body solder. Special lead—antimony alloys containing 1—4 wt % antimony are used for wheel-balancing weights, battery cable clamps, collapsible tubes, and highly machined isotope pots. 

Wrought lead—calcium—tin alloys contain more tin, have higher mechanical strength, exhibit greater stabiUty, and are more creep resistant than the cast alloys. RoUed lead—calcium—tin alloy strip is used to produce automotive battery grids in a continuous process (13). Table 5 Hsts the mechanical properties of roUed lead—calcium—tin alloys, compared with lead—copper and roUed lead—antimony (6 wt %) alloys. 

Demand for high performance SLI batteries has led to the development of smaller, lighter batteries that require less maintenance. The level of antimony is being decreased from the conventional 3—5% to 1.75—2.75% to minimise the detrimental effects. Lead alloys that contain no antimony have also been introduced. Hybrid batteries use a low antimony—lead alloy in the positive plate and a calcium—lead alloy in the negative plate. 

The wireless pH capsule (Medtronic Inc.) is oblong in shape and contains an antimony pH electrode, a reference electrode at its distal tip, a battery, and a RF transmitter. The whole device is encapsulated in epoxy. The capsule is introduced into the esophagus on a catheter through the nose or mouth and is attached to the lining of the esophagus with a clip. The probe monitors the pH in the esophagus and transmits the information via RF telemetry at a rate of 6 per second (0.17 Hz) to a pager-sized receiver that is worn by the patient on a belt. Prior to implantation, the capsule is calibrated with its receiver in pH buffer solutions of pH 1.07 and pH 7.01 [168],... 

Silver is employed for low resistance electrical contacts and conductors, and in silver cell batteries. Antimony is used in lead add storage batteries to improve the workability of the lead and lead oxides. Copper and copper alloy wires, connectors, cables, switches, printed drcuit boards, and transistor and rectifier bases are common throughout the industry. Nickel is used in high resistance heating elements, glass-to-metal seals, batteries, and spedalty steels for power generation equipment Household appliances employ stainless and electroplated steel containing nickel. 

Hardened with a little antimony it is used in storage batteries or accumulators, for cables, and occasionally for statuary. For this last, however, it is not really suitable its dull colour is not prepossessing. Bullets, etc, are made of lead hardened with 4 to 12 per cent of antimony. Other important alloys are solder (p. 212), type metal (p. 197) and bearing metals, which contain also tin and antimony. 

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