Conventional lead-acid battery

Most of the above modes of failure can be suppressed to an acceptable level in conventional lead-acid batteries, as follows. 

The chemistry of these batteries is that of conventional lead-acid batteries. However, they have a unique characteristics. The oxygen generated on overcharge is recombined in the cell and there is no water loss. Indeed, oxygen reacts at the negative electrode ... 

An all-plastic battery may have many advantages [26]. For example, a car battery made of polyacetylene could weigh only one-tenth of that of a conventional lead-acid battery. Moreover, batteries with plastic electrodes could be fabricated into odd shapes, such as a flat disc that could be slotted into a car door. Prototype batteries have been made using polyacetylene and poly-p-phenylene electrodes, but a number of technical problems, such as long-term mechanical integrity need to be solved. 

P-Alumina is used as an electrolyte in high-energy-density Na-S batteries. The concept of a battery based on the reaction of Na and S was first proposed in 1967 as an alternative to the conventional lead-acid battery. The Na and S are separated by a membrane of P-alumina, usually in the form of a closed-end thin-walled tube as shown in... 

As mentioned above, conventional lead-acid batteries were used at fully charged state and were only discharged at the time when need. However it is considered that those will be used more like cyclic use for industrial and automotive in the future. 

Because of its high energy density (Table 7.5), the NaS battery has also been proposed for outer-space applicahons, as these cells can be made space-hardened. In fact, in November 1997 a test sodium sulfur cell was flown on the STS-87 Space Shuttle mission to demonstrate its operation in space. The experimental battery had a mass energy density of 150 W hkg (threefold the energy density of a nickel hydrogen battery and about eightfold that of a conventional lead-acid battery) and, when operated at 350 °C, performed sahsfactorily over a 10-day period whilst in orbit... 

Table 7.5 Comparison of a typical NaS battery and a conventional lead-acid battery (Kamibayashi, 2001).

In the field of conventional lead-acid batteries the designation of discharging/ charging currents expresses the duration of discharge. So Iio and I5 mean the current that results in ten and five hours duration of discharge, respectively. These discharge currents are specified for the various types. 

In order to guarantee an almost maintenance-free operation of lead-acid batteries, which requires low decomposition rates of water, the usage of materials with high values of hydrogen overvoltage is needed. While lead basically fulfills that requirement, antimony, which is used more or less as an alloying component in conventional lead-acid batteries, decreases the overvoltage extremely. 

In contrast to conventional lead-acid batteries, valve-regulated batteries do not require free space underneath the plates for mud collecting, because loosened mass particles are fixed between the plates and cannot fall to the bottom of the cell, forming short circuits. In valve-regulated batteries, this space can be used for increasing the plate length in order to increase the capacity. 

Because valve-regulated gel batteries are not damaged by partial charging, which is forbidden for conventional lead-acid batteries. Partial charge operations are allowed if after every five cycles the battery is fully charged again. 

Valve-regulated lead-acid batteries are used today in almost all applications which are applicable for conventional lead acid batteries. Since these batteries generation was basically for portable batteries, this is still a market today, for instance in the medical area. Larger types, which were developed about 20 years ago, have a wide field in military applications. Since the 1980s modern tanks and military shelters have been equipped with the 123-V 100-Ah NATO type. Its advantage besides the high deep discharge ability is the maintenance-free behavior, especially due to the limited space conditions in modern tanks. 

Conventional lead-acid batteries are suited for various aerospace and other military applications, excluding compact aircraft applications, for which safety and reliability... 

Axion has stated that the PbC battery has several key performance advantages over conventional lead-acid batteries ... 

A bipolar lead-acid battery eliminates grouping of positive and negative plates and the connections between cells. Bipolar battery construction shortens the current path between the positive and negative terminals of the battery, which reduces the battery s internal resistance to current flow and improves power delivery. The bipolar battery configuration is particularly suitable for high-voltage batteries because bipolar construction requires less space compared to conventional lead-acid batteries. 

An electrolyte with a low sodium silicate concentration was developed to overcome the disadvantages of conventional lead-acid batteries and gel lead-acid batteries. A conventional lead-acid battery uses a sulfuric acid electrolyte, which is a health hazard and pollutes the environment. A gel lead-acid battery has disadvantages of difficulty in filling the gel electrolyte, crack and hardness of the electrolyte, low fluidity, and high internal resistance. 

Lead-acid batteries produce hydrogen and oxygen gases internally during charging and overcharging. These gases are released in an explosive mixture from conventional lead-acid batteries and therefore must not be allowed to accumulate in a confined space. An explosion could occur if a spark were introduced. 

Conventional lead-acid batteries contain a positive electrode (Pb02 plate) and a negative electrode (Pb plate) immersed in a sulfuric acid electrolyte and having a separator interposed between each plate. Such electrodes are typically made by applying a paste containing lead oxides and lead sulfates to the surface of a battery plate and electrochemically forming the paste into an active material. 

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