China's refined lead exports hit their lowest since September 2022 last month as a lack of raw material limited domestic production, and are expected to stay depressed for at least a few more months, industry participants said on Monday.

In June China exported 1,362 metric tons of refined lead, a 91% drop from last June's 15,215 tons, customs data released on Saturday showed.

At the same time, imports of the metal leaped to the highest since August 2023 at 525 tons, the data showed.

"Shortage of lead concentrate and lead battery (scrap) caused low margins or financial loss for smelters, resulting in widespread cutbacks at smelters in China," said analyst Dina Yu at consultancy and research firm CRU Group.

Lead output in China fell 3.7% year-on-year in the first half of this year to 3.88 million tons, data by the National Bureau of Statistics of China showed. In contrast, output rose 4% in 2022 and surged 11.2% in 2023, the data showed.

Refined lead imports were driven higher by the price difference between the Shanghai Futures Exchange (SHFE) - China's main futures market for base metals - and the global benchmark bourse the London Metal Exchange (LME).

"The recent rise in SHFE lead prices is stronger than the rise in LME lead prices, leading to negative arbitrage for lead exports and benefit for refined imports," Yu added.

A China-based trader said they had received a rising number of purchase orders, but that there was not enough cargo to meet demand.

Lead is the best performer across the base metals complex on the SHFE, up 25% so far this year, followed by tin at 19% and copper at 9%. Its most-traded front-month contract hit a record high on July 18 at 19,595 yuan ($2,694) a ton.

The LME three-month lead contract, on the other hand, has risen only 3% so far this year.

Tight concentrate supply globally had dragged the treatment charges (TC) for lead in China to 600 yuan a ton by July 1, the lowest in four years, monthly Shanghai Metals Market (SMM) data provided on LSEG Workspace showed.

TCs for imported lead concentrate fell even lower, to $10 a ton, by July 1, the lowest since at least 2014, the SMM data showed.

Chinese buyers have also imported more lead bullion - a lower-grade refined lead - as an alternative source of raw material, Yu said.

Customs data showed China imported 6,010 tons of lead bullion in June, the highest since July 2019.

Yu and two traders expected the higher lead imports and lower exports trend to continue, and possibly to intensify in July.

($1 = 7.2730 Chinese yuan renminbi)

(Reporting by Mai Nguyen in Hanoi; Editing by Jan Harvey)