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Relationship between current and negative-plate/positive-plate overpotential at 45 • C for cells prepared from control oxide and from oxides of specification I or specification II.
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Raw lead materials contain many residual elements. With respect to setting ‘safe’ levels for these elements, each country has its own standard, but the majority of the present specifications for the lead used to prepare battery oxide apply to flooded batteries that employ antimonial grids. In these batteries, the antimony in the positive and negati...
Citations
... Reduced setups are used also for gas tests (GTs) during water loss tests, where the Hydrogen Evolution Reaction (HER) and the Oxygen Evolution Reaction (OER) are detected by the volume variation and the monitoring of the vented gas rate. Unfortunately, LSV, CV, and GT characterization are often limited to electrodes with small surfaces, far even from the dimension of a single plate of an LAB, and at the same time, gas-developed quantification is very long, which means that it takes at least 10 h [43][44][45][46]. Combining all these aspects, the author of this chapter has recently published a fast method to predict water consumption behavior [47]. ...
Battery-based energy storage systems with high power/energy densities and excellent cycle efficiency are expected to play a key role in our everyday lives. Even though Lead-Acid Batteries (LABs) are the oldest electrochemical energy storage technology, they still attract a lot of interest thanks to their properties: stability, reliability, recyclability, and low cost of the raw materials. Precisely for these reasons, LAB technology will retain its strong position at least until 2030 and remain very competitive, but ongoing investments are needed to improve production and performance. The main weak points of LABs are the limited charge efficiency and cyclability, mostly due to the degradation of electrodes during the charging/discharging process. Corrosion, in particular, represents a severe problem for LABs and has been the subject of many studies. Although LABs inevitably corrode to a certain extent throughout life, runaway corrosion of the positive grid will ultimately lead to failure. This phenomenon results in capacity degradation, often termed “Premature Capacity Loss” (PCL) or in electrical shorts. This chapter, after having given a general overview of LABs, describing their different types, their chemistry, and their failure modes, focuses specifically on the problem of corrosion of the grids stressing the causes of this phenomenon and the different strategies to evaluate and reduce it.
... [11] In addition, it was examined that the presence of Sn as a residual element in active material showed beneficial effect on gassing. [12] In recent years, the use of conductive CF as additives in lead acid batteries have increased due to their low weights and enhanced specific surface areas. The effects of CF on performance are particularly important when the high-rate partial state of charge (HRPSoC) operated. ...
The enhancement of battery performance becomes one of the crucial points of the current research. In this study, the effect of zinc (Zn), tin (Sn), and lead (Pb) electrodeposited on carbon fibers (CF), and pristine‐CF on the negative plates of the lead acid batteries are investigated instead of the traditionally used polypropylene (PP) fibers as additives. The morphological and structural properties of the samples were characterized by scanning electron microscopy (SEM) and X‐ray diffraction spectroscopy (XRD). The electrochemical performance of the 2 V/30 Ah enhanced flooded cells were prepared and tested. The 50 % depth of discharge (DoD) cycles were carried out. Constant charging processes were applied at 60 °C for 42 days for water consumption tests. Although the best cyclic performances were recorded from the cells with pristine‐CF and CF/Zn, due to enhanced water‐loss in those samples, acidity was increased. On the other hand, with the addition of CF/Sn and CF/Cu/Pb, gassing is reduced resulting in acid stratification during charge/discharge process leading to lower cycle performance, eventually. Overall, using CF or metal modified CF instead of PP fibers enhances the number of charge‐discharge cycle by at least 23 cycles.
... This difference can be associated with a tendency toward agglomeration and stacking, which 2D carbons have due to the strong interactions of van der Waals [27]. Thus, the actual number of layers for the samples were used only to estimate the causes related to the observed performance parameters (nominally the layer numbers are G10: [1][2][3][4][5][6][7][8][9][10], G20: [20][21][22][23][24][25][26][27][28][29][30], G50: [50-60]). In fact, a method of dispersing the particles of these materials was later necessary, before using them as additives in lead-acid batteries. ...
... As electrolysis reactions are greatly influenced by the amount of metal ions present [30,31] and many carbons contain residual amounts of iron and other harmful elements in their composition [32], which can arise either from their source of obtaining, and the processing method, the use of carbonaceous additives in such small amounts would have an equally reduced effect. This is one of the great advantages of using ultratrace concentrations, particularly on an industrial scale. ...
... On the other hand, the water consumption effect in reduced size configuration is mainly detected through Cyclic Voltammetry (CV) or Linear Sweep Voltammetry (LSV) using a third electrode (reference), in order to investigate the reactions governing the water consumption of the single plate (either negative or positive) or to determine the inhibition and the retarding behaviour toward the H2/O2 evolution caused by additives/contaminants in electrolyte and plate compositions [16][17][18][19][20][21] . Non-conventional designs, namely reduced size cell, are used also for the gas quantification during floating water consumption tests, where the Hydrogen Evolution Reaction (HER) and the Oxygen Evolution Reaction (OER) are detected by the volume variation and the monitoring of vented gas rate [19,[22][23][24][25][26][27][28][29] . Unfortunately, LSV, CV and GT characterization are often limited to electrode with small surface, far even from the dimension of a single plate of a lead acid battery. ...
... Unfortunately, LSV, CV and GT characterization are often limited to electrode with small surface, far even from the dimension of a single plate of a lead acid battery. Moreover, when massive plate are used in reduced cell, the time required for the gas developed quantification is very long, that means that it takes at least 10 hours [24] . To the best of our knowledge, no work in the literature has yet combined the information deducible from voltametric techniques, with the determination of gassing rates in floating overcharging tests. ...
The main failure processes in flooded lead–acid batteries associated to the gradual or rapid loss of performance, and eventually to the end of service life are: anodic corrosion of grids, positive active mass degradation coupled with loss of adherence to the grid, irreversible formation of lead sulphate in the active mass, short‐circuits, and loss of water. Generally, the rates of the different aging processes depend strongly on the operational condition of the battery. However, the presence of certain additives or contaminants (coming from raw material or from their processing) may prompt or anticipate the aging mechanisms and also make the entire batches of manufactured batteries unusable and unsalable. Unfortunately, contaminants and additives effects on aging processes are difficult to predict. Specifically for the water loss estimation, the European standard CEI EN 50342‐1:2019‐11 requires a water consumption test in which the weight loss (WL) is measured on a 12 V battery, submitted to a floating charge (potential continuously applied to the battery terminals) at 14.40 V in a 60 °C bath for at least 21 days. Such long period can pose economical and sustainability concerns for FLAB production sector constrained in strict deadlines and market requests. Furthermore, the WL method is not informative about the reasons of the water consumption and not less important, it does not reveal possible side reactions such as carbon materials degradation or positive grid corrosion.
... The multiple-valence iron is considered to generate fatal effects to the battery capacity, leading to corrosion of the electrodes, which in turn causes loss of active materials, as well as promotes selective discharge, undesirably releasing oxygen and hydrogen gases. The resulting effect of iron contamination can be understood as a decrease in the battery life cycle (Lam et al. 2010). ...
This work presents an inter-loop approach as an environmental solution in which the hydrothermal carbonization (HTC) of sewage sludge allows the production of hydrochars capable of removing iron ions, which usually harm the lead-acid batteries performance, from spent sulfuric acid. The HTC process was performed at three different water/biomass ratios under mild experimental conditions, and except for water, no additional chemical input was used. The moisture content of the sludges was set to range between 76 and 91 wt.%. Hydrochars were characterized by XRD, FTIR, SEM, TGA, and N2 adsorption–desorption techniques. Results suggest a high dependence of their textural and surface properties on the water/biomass weight ratio inside the reactor. The expressive presence of multiple mineral phases in the sewage sludge allowed the formation of a hydrophilic surface, which was fundamental for the adsorption of iron ions under strong acidic conditions. Porosity was also strongly influenced by the water/biomass weight ratio, with the hydrochar’s surface displaying pore dimensions in nano- and micro-domains. Furthermore, the hydrochar presented an adsorption capacity up to 148 mgFe g−1 without any activation step, whereas the ordinary commercial activated carbon achieved 178 mgFe g−1. Results show the potential of the HTC process for sewage sludge conversion into hydrochars without pre-drying, and the possibility of interconnecting two or more industrial processes in order to make them cleaner and more sustainable, matching the principles of the circular economy.
Graphical abstract
... However, antimony dissolves in the electrolyte, migrates to the negative electrode, and promotes hydrogen evolution during standby, charge and overcharge. Hence for maintenance-free batteries, low antimony positive grid alloys are used, while for VRLA, antimony free alloys of Pb-Ca-Sn are used [19,21], with calcium providing mechanical strength and tin mitigating grid corrosion, while Pb-Ca alloy is used for the negative gird. Positive active material softening and shedding, and negative active material sulfation, common to flooded and VRLA batteries, are covered in detail in the next section. ...
... Oxygen recombination depolarizes the negative electrode, thus raising its potential. For batteries charged at a constant potential, this raises the positive electrode potential, leading to greater positive grid corrosion, with associated water loss [19,21] and additional oxygen evolution, which corrodes the grid further [12]. The higher sulfuric acid concentration due to water loss accelerates grid corrosion [19]. ...
This work highlights the performance metrics and the fundamental degradation mechanisms of lead-acid battery technology and maps these mechanisms to generic duty cycles for peak shaving and frequency regulation grid services. Four valve regulated lead acid batteries have been tested for two peak shaving cycles at different discharge rates and two frequency regulation duty cycles at different SOC ranges. Reference performance and pulse resistance tests are done periodically to evaluate battery degradation over time. The results of the studies are expected to provide a valuable understanding of lead acid battery technology suitability for grid energy storage applications.
... Regarding to the relatively high content of Ca in the Pb 3 O 4 product, it has no significant negative impact on the battery performance (Lam et al., 2010;Pavlov, 2011). As for Sb, previous studies had demonstrated that the Sb 2 O 3 additive could improve the contents of hydrated PbO 2 in PAMs, resulting in a longer cycle life of LAB . ...
Hydrometallurgical process for recovery of spent lead-acid battery paste shows great advantages in reducing SO2 and lead particulates emissions than traditional pyrometallurgical process. However, the hydrometallurgical process usually has drawbacks of high consumption of chemical reagents and difficulty in removing impurities (especially Fe and Ba elements) from the recovered product. In this paper, a closed-loop ammonium salt system is proposed for spent lead-acid battery paste recovery. Both recirculation of leaching reagents and preparation of low-impurity recovered products have been realized. The spent lead paste is first leached by a mixed solution of ammonium acetate, acetic acid and hydrogen peroxide. After filtration, the separated lead acetate solution is reacted with ammonium carbonate to generate lead carbonate via precipitation process. The impurity elements are efficiently removed by pH control and complexation between acetate ions and impurity elements in the leaching and precipitation processes. The soluble SO4²⁻ separated from the precipitation process is removed by adding barium acetate to generate solid BaSO4 by-product. At the same time, the regenerated ammonium acetate filtrate is separated and re-used in the next-round leaching process in order to realize a closed-loop process. In the 5th round of filtrate recirculation processes, the leaching ratio of lead is maintained at levels higher than 92.7 wt%. Furthermore, high-purity lead tetroxide is prepared by calcination of lead carbonate in air at 450 °C. The contents of Fe and Ba in the final recovered lead tetroxide product are as low as 2.7 and 5.2 mg/kg, respectively. The recovered lead tetroxide product meets the specifications for use as an additive in the positive active materials for making a new lead-acid battery. This study provides a feasible technology for high-value utilization of spent lead paste.
... Some impurities are inevitably introduced and remained in leady oxide after hydrometallurgy recovery process, such as Fe, Sb, Cd and Cu. 23 Among them, the contents of Fe and Sb are highest. Fe is a commonly harmful element in LABs, while Sb is widely used in lead grid to enhance the mechanical properties. ...
... It is in agreement with the results reported in the literatures that Fe is a harmful element for LABs and its concentration should be lower than 10 ppm. 23 And the amounts of PbSO 4 increases with the increasing of Fe content in the positive plates, resulted in a lower porosity and specific surface area in the PAM with Fe impurity after 50 discharge cycles. 27 The change of discharge capacity for the Sb-doped novel leady oxide is shown in Fig. 6. ...
... The CV and discharge capacity result is in agreement with the previous study that proper amount of antimony is beneficial to the performance of lead-acid batteries. 23 Excessive loading of antimony doping will deteriorate the performance of lead-acid batteries due to higher gassing rate, water-consumption and corrosion of plates. 28,29 However, there is no significant difference between capacity of plates within various content of Sb doping after 40 cycle numbers. ...
A rapid electrochemical assessment of the performance of novel leady oxide is demonstrated to provide an alternative route for the time-consuming battery tests. The leady oxide is recovered from spent lead pastes with different level of Fe and Sb doping. The rapid electrochemical assessment for leady oxide acting as positive active materials (PAMs) of a lead-acid battery (LAB) is conducted via cyclic voltammetry (CV) using a three-electrode system. The working electrode is the novel leady oxide which was coated on the current collector of glassy carbon. The current density and discharge capacity increase rapidly at first, then decrease and finally tend to be stable gradually. The rising and falling parts of the CV curves indicate the forming and discharging processes, respectively. The imax cycle and the discharge capacity of leady oxide in CV tests are proved to be ideal indicators of the initial capacity and cycle performance of a fabricated battery. Based on this rapid assessment method, the effects of iron and antimony on electrochemical performance of leady oxide have been clarified. This electrochemical evaluation procedure only takes less than 2 days, and the electrochemical performance of leady oxide represents the procedure of formation and cycling as a lead-acid battery.
... Many researchers have studied the effects of impurities on the performance of the LABs. Lam et al. have studied the effects of seventeen elements including Sb, As, Bi, Cd, Cr, Co, Cu, Ge, Fe, Mn, Ni, Se, Ag, Te, Ti, Sn, and Zn on the oxygen-and hydrogen-gassing rates of LABs [101]. The iron is confirmed as the major "harmful element" because it promotes the hydrogen and oxygen gassing rates of LABs. ...
... The conventional pyrometallurgical process could remove the impurities easily through refining process based on different melting points of different metals. The standard of impurity elements for metallic lead used in lead-acid battery manufacturing has been reported in the literature [91,101]. The specific limits of impurities are different in different countries or companies. ...
... There is no standard specification for impurity elements in leady oxide. Fortunately, some studies give the impurity limits of the leady oxide for lead-acid battery manufacturing, which are shown in Table 4 [21,101]. The maximum acceptance levels of Fe, Sb, Cu, and Zn elements in leady oxide for valve-regulated lead-acid battery (VRLA battery) are 10, 5, 34 and 500 mg/kg, respectively. ...
Emissions of lead particulates, sulfur oxides and their potential environmental risks are received great attention in traditional pyrometallurgical process for recycling spent lead-acid battery. In recent years, environmentally- friendly processes operating at near ambient temperatures show a good prospect for the recovery of spent lead- acid batteries, including electrowinning, organic acid leaching-calcination, and alkaline leaching-crystallization processes. The recovered products such as leady oxide (mixture of PbO and metallic Pb) and pure lead oxide from hydrometallurgical processes could be directly re-utilized as active materials in manufacturing of new batteries. A hydrometallurgical recovery route can eliminate the smelting procedure for lead ingot production and the following steps of Ball-milling or Barton liquid lead atomizing for leady oxide production in conventional lead mass flow from spent lead-acid battery to new lead-acid battery. Two technological challenges in hydrometal-lurgical recovery process for spent lead-acid battery are recognized as: removal of impurity elements (such as Fe and Ba) and loop reuse for reducing dosage of leaching reagents. Bibliometric analysis of recovery of spent lead- acid battery based on recent publications from 1987 to 2018 shows that the organic acid leaching-calcination process is the most frequently published technology in hydrometallurgical processes, meanwhile leady oxide and lead oxide are the most recovered products.
... Generally, the content of Fe in the metallic Pb recovered through the traditional pyrometallurgical route with refining process was < 10 mg kg -1 . 18 The Fe impurity with such low content has no evident impact on the phase composition of positive material during battery manu-facturing. However, regarding to the hydrometallurgical process, it is a challenge to efficiently remove Fe impurities during the recovery process. ...
... Besides, the increased hydrogen and oxygen gassing rate caused by Fe impurity aggravated the PAM expansion and shedding during the charge-discharge cycles. 16,18 Therefore, the premature capacity loss of the testing cell was observed when the Fe element impurity content in the leady oxide was only 49 mg kg -1 of LO-0.005. ...
Leady oxide samples with various Fe contents were recovered from simulated spent lead paste with the addition of various dosages of iron oxides as simulated Fe impurities via hydrometallurgical process with sodium citrate-acetic acid solution. More than 75 wt% of the Fe element in simulated spent lead paste remained in the recovered leady oxide. The recovered leady oxide samples were used to prepare positive plates in order to illuminate the effect of Fe impurities on the phase composition of positive material. When the Fe content in recovered leady oxide was > 223 mg kg⁻¹, the generation of 4PbO·PbSO4 (4BS) during curing procedure was inhibited. The specific surface area, α-PbO2 content, and hydrated PbO2 content of positive active mass (PAM) after formation procedure decreased with the increase of Fe content. As a result, larger PbSO4 crystals formed in Fe-containing PAMs after cell discharge, which hindered the transfer of H2SO4 electrolyte and destroyed the interconnected PbO2 skeleton. The negative effect of Fe impurities on cell cycle performance was observed when the PAM was manufactured from the leady oxide containing only 49 mg kg⁻¹ Fe element, with the cell capacity decreased from 2.2 to 1.0 Ah after only 230 charge-discharge cycles.
