Optimization of the positive active material capacity in lead-acid cells through control of the basic lead sulfate precursor

Journal Article · Thu Oct 01 04:00:00 EDT 1998 · Journal of the Electrochemical Society

DOI:https://doi.org/10.1149/1.1838812· OSTI ID:659166

Grugeon-Dewaele, S; Laruelle, S; Tarascon, J M; Delahaye-Vidal, A ^[1]; Torcheux, L ^[2]

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1. Lab. de Reactivite et de Chimie des Solides, Amiens (France)
2. CEAC, Gennevilliers (France)

The mechanisms for the 3PbO{center_dot}PbSO{sub 4}{center_dot}H{sub 2}O (denoted 3BS) {yields} PbO{sub 2} and 4PbO{center_dot}PbSO{sub 4} (denoted 4BS) {yields} PbO{sub 2} transformations were studied from well-defined, pure samples formed in a laboratory cycling test cell. The oxidation reactions were observed using X-ray diffraction and scanning electron microscopy (SEM). No structural memory effect was found between 3BS and PbO{sub 2} since the 3BS {yields} PbO{sub 2} reaction occurred through a dissolution recrystallization process. In contrast, textural relationships between needle-shaped 4BS and PbO{sub 2} were evidenced by SEM analyses. Indeed, 4BS was found to transform into PbSO{sub 4}, which in turn transformed into PbO{sub 2} while retaining the needle shape as long the reaction proceeded. The thickness of the PbO{sub 2} needle crust surrounding /the 4BS needle core was found to depend on both the temperature and soaking duration. A model predicting a decrease in the capacity with the increase in the needle thickness, as a consequence of the inactive 4BS presence inside the needles, is proposed. The ability to prepare samples of controlled morphology revealed a decrease in capacity with the increase in the needle thickness, thereby confirming the model prediction. But more importantly, the authors showed that a 20--25% increase in the positive electrode efficiency could be achieved by reducing the thickness of the usual 4BS cured industrial samples from 10--15 to 3--4 {micro}m.

• Sponsoring Organization: USDOE
• OSTI ID: 659166
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 10 Vol. 145; ISSN 0013-4651; ISSN JESOAN
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
36 MATERIALS SCIENCE
CATHODES
ELECTRICAL PROPERTIES
ELECTROCHEMISTRY
LEAD OXIDES
LEAD SULFATES
LEAD-ACID BATTERIES
MATHEMATICAL MODELS
MICROSTRUCTURE