Lead-acid batteries impact

The conductivity of the grid plays a substantial role in a battery s abiUty to meet high current demands. The importance of grid conductivity for lead—acid batteries has been discussed (1,69). Composition and configuration are important design factors impacting grid conductivity. 

R. T. Johnson and. R. Pierson, "The Impact of Grid Composition on the Performance Attributes of Lead—Acid Batteries," iu L. J. Pearce, ed.. Power Sources 11, International Power Sources Symposium Committee, 1987. 

The energy costs of building vehicles must also be considered. For ICE vehicles, more energy is usually used in construction of the vehicle than -will be consumed in fuel for driving 100,000 miles. For the EV, the dynamics are even worse since the material and energy costs of batteries are considerable. Batteries are expensive since they entail a substantial amount of material (added weight) and often involve multiple complex construction. For example, the thirty-two advanced lead-acid batteries for the 1995 GM Impact weighed over 850 pounds. 

Research the impact of lead pollution on the environment. Do lead-acid batteries contribute significantly to lead pollution ... 

Previously, the U.S. EPA had specifically promulgated regulations that exempted used lead acid batteries from the regulatory burdens of RCRA in order to facilitate the already well-established recycling of automotive batteries. As a result, lead acid batteries enjoyed a recycling rate of better than 95%. NiCd batteries, however, were not included in this earlier scheme, and at the time the TCLP test was initiated, its potential impact on NiCd batteries was not recognized and no provisions were made to facilitate their recycling. 

Because the market for lead-acid batteries is already extremely large, even a significant penetration of the EV application by this battery chemistry is not expected to have a noticeable impact on the ability of industry to continue the present high recycling rate. A study was conducted in 1996 and confirmed this low impact of increased EV use on... 

Nevertheless, the assumptions were conservative in the sense that the predictions based on them likely represent an upper limit for the impact on the lead-acid battery recycling industry. The mass of lead in scrap EV batteries is projected to increase as shown in Figure 9, reaching about 16,000 metric tons in 2005. This can be compared to Figure 10, which shows the amount of lead from battery scrap and the total amount of lead recovered from scrap in the U.S. through the year 1995 from U.S. Bureau of Mines data. Total secondary lead is nearing IM metric tons per year. The predicted EV battery lead mass in 2005 is only about 1.5% of the secondary lead recovery capacity in 1996 and will actually be less than that in 2005 once the future growth in secondary lead recovery is included. Clearly EV battery waste will remain a very small portion of secondary lead production well beyond 2005. 

The relatively heavy weight of lead-acid batteries in relation to the useable performance has advantages for forklift trucks and other tractors (as counterweight or ballast), but is a great disadvantage for other traction systems such as electric road vehicles and mobile electric power supplies. Results in development with the aim to increase the specific energy and performance of battery systems and the minimization of their maintenance also have an impact on the employment of vehicles for materials handling. 

Capacity indicators for traction batteries are on the market in many variants, of different reliability, and adapted to different battery types. This is understandable since the useful capacity of a lead-acid battery is dependent on several parameters, such as physical and chemical impacts, design and type of the battery, aging, temperature, and load. The user s demand in any case is to have a capacity indicator, comparable with a fuel indicator in a motorcar. 

Table 7.2 Impact of Depth of Discharge on Life Cycle of Lead-Acid Batteries at 50 A Charge Current...

The electromotive force of the cell with no ion transfer (AE ) is 2.040 V and it is determined on the basis of Gibbs free energies of the products and reagents participating in the reaction. The concentration of H2SO4 and the temperature of the cell will also impact the cell electromotive force. The open cell potential for lead-acid batteries is 2.10 to 2.13 V and the nominal voltage of a single practical lead-acid battery is 2 V. 

General Motors are continuing to develop the Impact lightweight electric car. This vehicle is capable of accelerations of 0 to 60 mph in 8 seconds and has a top speed of 100mph. It is fitted with 3210 V lead acid batteries weighing 396 kg. 

Total life cycle analyses may be utilized to establish the relative environmental and human health impacts of battery systems over their entire lifetime, from the production of the raw materials to the ultimate disposal of the spent battery. The three most important factors determining the total life cycle impact appear to be battery composition, battery performance, and the degree to which spent batteries are recycled after their useful lifetime. This assessment examines both rechargeable and non-rechargeable batteries, and includes lead acid, nickel cadmium, nickel metal hydride, lithium ion, carbon zinc and alkaline manganese batteries. 

Unlike lead-acid and silver oxide batteries, which have historically been collected and recycled due to their economic value, collection and recycling of general purpose batteries is currently undertaken at a cost to the waste generator. All responsible manufacturers whatever the industry, recognise a need to protect the environment and promote sustainable development. However this is rarely possible at zero cost. In the late 1980 s many battery systems still contain a significant proportion of toxic elements whose environmental impact after use needed to be controlled. 

In Europe, the drive system of the Impact propelled the Opel Impuls2, a conversion vehicle based on the Opel Astra Caravan in 1991. A new, specifically developed AC induction drive unit with IGBT inverter technology was used to build a small fleet of Impuls vehicles see Figure 8.4). The fleet served as an automotive test bed for the integration of various advanced battery systems such as nickel-cadmium, nickel-metal hydride, sodium-nickel chloride, sodium-sulfur, and sealed lead-acid. 

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