Environmentally assisted cracking of nickel strip in LiAlCl{sub 4}/SOCl{sub 2}

Journal Article · Fri Sep 01 04:00:00 EDT 1995 · Journal of the Electrochemical Society

DOI:https://doi.org/10.1149/1.2048673· OSTI ID:122723

Wasynczuk, J A; Quinzio, M V; Bittner, H F ^[1]

---

1. Aerospace Corp., Los Angeles, CA (United States)

Constant extension rate tests (CERT) were used to evaluate the susceptibility of two cold-rolled nickel strip materials to environmentally assisted cracking (EAC) in 1.5M LiAlCl{sub 4}/SOCl{sub 2}. One strip material was made by a powder metallurgy (PM) process that started with carbonyl nickel. The other was cast and wrought (C/W). Both were 0.05 mm thick and cold-rolled to the three-quarter hard condition. The bulk impurity concentrations, grain structures, and mechanical properties of these two materials were similar. However, the C/W alloy was distinguished by a substantially higher bulk manganese content and oxygen-rich inclusions, a large fraction of which also contained sulfur. EAC of the PM alloy, manifested principally as intergranular fracture, occurred in samples that were polarized to {minus}50, 0, and +200 mV (Li/LiCl) but not in ones that were freely corroding at +3.65 V (Li/LiCl). These results are consistent with EAC being caused by a mechanism involving zero-valent lithium, proposed by Scully et al. In marked contrast to the PM alloy, the C/W alloy exhibited no susceptibility to Li-assisted cracking. In ancillary experiments, performed with samples that were cathodically charged with hydrogen, only the PM alloy exhibited a high susceptibility to intergranular cracking. The present results indicate that subtle microstructural differences may affect the reliability of Li/SOCl{sub 2} cells. Although the existing evidence is circumstantial, the results also suggest that lithium-assisted and hydrogen-assisted intergranular cracking have analogous sensitivities to grain boundary segregation of sulfur.

• Sponsoring Organization: USDOE
• OSTI ID: 122723
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 9 Vol. 142; ISSN JESOAN; ISSN 0013-4651
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
36 MATERIALS SCIENCE
ALUMINIUM CHLORIDES
CONNECTORS
CORROSIVE EFFECTS
CRACK PROPAGATION
FABRICATION
HYDROGEN EMBRITTLEMENT
INTERGRANULAR CORROSION
LITHIUM CHLORIDES
LITHIUM-SULFUR BATTERIES
MICROSTRUCTURE
NICKEL
RELIABILITY
THIONYL CHLORIDES