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G Petkova - One of the best experts on this subject based on the ideXlab platform.
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phenomena that limit the capacity of the Positive lead acid battery Plates i the charge potential transient as an indicator of Positive Plate state of charge and state of health
Journal of The Electrochemical Society, 2002Co-Authors: D Pavlov, G PetkovaAbstract:The capacity of the Positive Plate of the lead-acid battery is determined by the number of the active centers in Positive active material (PAM) where the reaction PhO 2 → PhSO 4 proceeds and by the resistance of the interface corrosion layer (CL) + AMCL (thin PAM layer interconnecting the PAM and the CL). It was established that the number of the active centers is high if the Positive Plate discharge is performed with low current and if the charge (at the initial period is performed with high current. During discharge the active centers from the outer layer of the Plate are exhausted and the reaction of the PbO 2 reduction approaches the inner part of the Plate near the interface and the interface itself. If the pH of the pore solution is low the reduction of the PbO 2 proceeds to PhSO 4 . At the subsequent charge with sufficiently high current a maximum appears on the potential transient. When the H 2 SO 4 flux to the interface is impeded, the pH of the solution in the pores in the interface is high and the reduction of the PbO 2 proceeds to PbD n (1 < n < 1.5). As the PbO n has high electrical resistance, during the subsequent charge with high current a peak appears at the beginning of the potential transient. Its height depends on the resistance of the interface. On the basis of the appearance of a maximum or a peak the state of change and the state of health of the Positive Plate can be determined.
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influence of fast charge on the life cycle of Positive lead acid battery Plates
Journal of Power Sources, 2000Co-Authors: D Pavlov, G Petkova, M Dimitrov, M Shiomi, M TsubotaAbstract:Abstract A criterion has been found for determination of the factor limiting the discharge of the lead dioxide Plate. When on discharge with moderate currents, an arrest or a shoulder appears between 1.0 and 0.7 V (vs. Hg/HgSO 4 electrode) in the potential transient, then the charging potential transient features a peak at the beginning of the curve. The capacity is limited by the interface. The life cycle of the battery is short. This phenomenon is known as PCL effect. When a broad maximum occurs in the potential transient on charge, this indicates that the electrode capacity is limited by zones of high resistance in Positive active mass (PAM) near the interface. The capacity is determined by the lead dioxide active mass. It has been established that the life of the Positive Plate is proportional to the current density during the initial charge stage. A sol–gel–crystal mechanism of the charge processes is proposed to explain this effect of fast charge on electrode life. The high rate of the electrochemical reaction leads to high oversaturations of the Pb(OH) 4 sol and to fast formation of gel–crystal PbO(OH) 2 /PbO 2 particles, which not only form new agglomerates tightly connected to the PAM skeleton, but also fill in and improve the contacts between the agglomerates. The latter process has the effect of “welding” of the PAM skeleton. Moreover, the higher concentration of the Pb(OH) 4 sol affects the macro- and microstructure of the PAM, which in turn has an influence on the electrochemical reaction. Impedance measurements have evidenced different values of the electron transfer resistance in electrodes charged at high and low currents.
D Pavlov - One of the best experts on this subject based on the ideXlab platform.
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phenomena that limit the capacity of the Positive lead acid battery Plates i the charge potential transient as an indicator of Positive Plate state of charge and state of health
Journal of The Electrochemical Society, 2002Co-Authors: D Pavlov, G PetkovaAbstract:The capacity of the Positive Plate of the lead-acid battery is determined by the number of the active centers in Positive active material (PAM) where the reaction PhO 2 → PhSO 4 proceeds and by the resistance of the interface corrosion layer (CL) + AMCL (thin PAM layer interconnecting the PAM and the CL). It was established that the number of the active centers is high if the Positive Plate discharge is performed with low current and if the charge (at the initial period is performed with high current. During discharge the active centers from the outer layer of the Plate are exhausted and the reaction of the PbO 2 reduction approaches the inner part of the Plate near the interface and the interface itself. If the pH of the pore solution is low the reduction of the PbO 2 proceeds to PhSO 4 . At the subsequent charge with sufficiently high current a maximum appears on the potential transient. When the H 2 SO 4 flux to the interface is impeded, the pH of the solution in the pores in the interface is high and the reduction of the PbO 2 proceeds to PbD n (1 < n < 1.5). As the PbO n has high electrical resistance, during the subsequent charge with high current a peak appears at the beginning of the potential transient. Its height depends on the resistance of the interface. On the basis of the appearance of a maximum or a peak the state of change and the state of health of the Positive Plate can be determined.
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influence of fast charge on the life cycle of Positive lead acid battery Plates
Journal of Power Sources, 2000Co-Authors: D Pavlov, G Petkova, M Dimitrov, M Shiomi, M TsubotaAbstract:Abstract A criterion has been found for determination of the factor limiting the discharge of the lead dioxide Plate. When on discharge with moderate currents, an arrest or a shoulder appears between 1.0 and 0.7 V (vs. Hg/HgSO 4 electrode) in the potential transient, then the charging potential transient features a peak at the beginning of the curve. The capacity is limited by the interface. The life cycle of the battery is short. This phenomenon is known as PCL effect. When a broad maximum occurs in the potential transient on charge, this indicates that the electrode capacity is limited by zones of high resistance in Positive active mass (PAM) near the interface. The capacity is determined by the lead dioxide active mass. It has been established that the life of the Positive Plate is proportional to the current density during the initial charge stage. A sol–gel–crystal mechanism of the charge processes is proposed to explain this effect of fast charge on electrode life. The high rate of the electrochemical reaction leads to high oversaturations of the Pb(OH) 4 sol and to fast formation of gel–crystal PbO(OH) 2 /PbO 2 particles, which not only form new agglomerates tightly connected to the PAM skeleton, but also fill in and improve the contacts between the agglomerates. The latter process has the effect of “welding” of the PAM skeleton. Moreover, the higher concentration of the Pb(OH) 4 sol affects the macro- and microstructure of the PAM, which in turn has an influence on the electrochemical reaction. Impedance measurements have evidenced different values of the electron transfer resistance in electrodes charged at high and low currents.
L Zerroual - One of the best experts on this subject based on the ideXlab platform.
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effect of a mineral additive on the electrical performances of the Positive Plate of lead acid battery
Journal of Power Sources, 2015Co-Authors: M Foudia, M Matrakova, L ZerroualAbstract:Abstract The objective of this work is to improve the performance of the Positive electrode of lead-acid battery. The use of the additive in the Positive paste is to increase the capacity and cycle life of the Positive active material. Mineral porous additives, dispersed uniformly in the PAM, may act as acid reservoirs and favor the ionic diffusion. The results show that the addition of mineral additive in the paste before oxidation influences the composition and the crystal size of the PAM after oxidation. We observe a remarkable improvement of the discharge capacity of the PAM for an amount of additive ranging between 1 and 5%. Nano-sized particles of PbO2 with amorphous character are obtained. XRD, TG and DSC, SEM, and galvanostatic discharge were used as techniques of investigation.
M Tsubota - One of the best experts on this subject based on the ideXlab platform.
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influence of fast charge on the life cycle of Positive lead acid battery Plates
Journal of Power Sources, 2000Co-Authors: D Pavlov, G Petkova, M Dimitrov, M Shiomi, M TsubotaAbstract:Abstract A criterion has been found for determination of the factor limiting the discharge of the lead dioxide Plate. When on discharge with moderate currents, an arrest or a shoulder appears between 1.0 and 0.7 V (vs. Hg/HgSO 4 electrode) in the potential transient, then the charging potential transient features a peak at the beginning of the curve. The capacity is limited by the interface. The life cycle of the battery is short. This phenomenon is known as PCL effect. When a broad maximum occurs in the potential transient on charge, this indicates that the electrode capacity is limited by zones of high resistance in Positive active mass (PAM) near the interface. The capacity is determined by the lead dioxide active mass. It has been established that the life of the Positive Plate is proportional to the current density during the initial charge stage. A sol–gel–crystal mechanism of the charge processes is proposed to explain this effect of fast charge on electrode life. The high rate of the electrochemical reaction leads to high oversaturations of the Pb(OH) 4 sol and to fast formation of gel–crystal PbO(OH) 2 /PbO 2 particles, which not only form new agglomerates tightly connected to the PAM skeleton, but also fill in and improve the contacts between the agglomerates. The latter process has the effect of “welding” of the PAM skeleton. Moreover, the higher concentration of the Pb(OH) 4 sol affects the macro- and microstructure of the PAM, which in turn has an influence on the electrochemical reaction. Impedance measurements have evidenced different values of the electron transfer resistance in electrodes charged at high and low currents.
Feroz Shah - One of the best experts on this subject based on the ideXlab platform.
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comparison of four different neutralizers for the treatment of acidic waste water
Journal of the Pakistan Institute of Chemical Engineers, 2017Co-Authors: Jamil Ahmad, Muhammad Afzaal Akram, Shehzad Khattak, Feroz ShahAbstract:Four different neutralizers i.e. 1N NaOH, NaOH 98 %, Ca(OH)2 and Na2CO3 were tested to neutralize acidic wash water samples from Positive Plates having pH 1,2 and negative Plates having pH 1, 2 from an automotive battery production plant. Comparison of the results shows that the minimum amount of neutralizer used was 1 N NaOH in the case of Positive Plate (0.052g) and negative Plate (0.016 g) wash water with initial pH of 2. This was followed by NaOH 98 % 0.06 g in the case of Positive Plate and 0.025 g in the case of negative Plate, then Ca (OH)2 of 0.08 g in the case of Positive Plate and 0.07 g in the case of negative Plate. The maximum amount used was that of Na2CO3 0.1 g both for the Positive and negative Plate wash water. For pH 1 Positive Plate wash water 1 N NaOH (0.285 g) was the minimum and NaOH 98 % (0.75 g) was maximum. However for the negative Plate wash water of pH 1 the trend was reverse i.e. NaOH 98 (0.215 g) was minimum and 1N NaOH (0.568 g) was maximum for bringing the pH of acidic waste water to a neutral value of 7.