SHANGHAI, May 15 (SMM) - Quotes of battery-grade nickel sulphate were 32,900-33,500 yuan/mt last Friday, down 700 yuan/mt from the previous Friday. SMM battery-grade nickel sulphate price index was 33,160 yuan/mt, down 739 yuan/mt WoW. The nickel sulphate transactions were slack last week since the ternary precursor companies still took a wait-and-see approach. According to SMM survey, the constant price decline in nickel sulphate crystals is attributed to the following three reasons. First, demand from the precursor companies stood low because the precursor producers’ production did not grow, and some even lowered their operating rates. Second, the small order transactions became more sluggish amid the huge gap between the offers and quotes. Third, nickel sulphate inventory held by nickel salt plants was high as the downstream companies were not active in picking up spots. And the producers had to cut their quotes to ship under the huge pressure from elevated inventory. However, the recent rebound in lithium salt prices has boosted the downstream manufacturers’ inquiries and purchases of nickel salt. Prices of nickel sulphate are expected to move between 32,000-34,000 yuan/mt this week.