SEOUL, April 29 (Reuters) - SK Innovation Co Ltd

, owner of South Korea's top refiner SK Energy, said

on Monday it expects solid refining margins to continue in the

second quarter backed by firm demand.

The company posted an operating profit of 625 billion won

($454 million) for the January-March period, versus a 375

billion won profit a year earlier. That compared with an average

analyst forecast of 466 billion won.

First-quarter revenue fell 1.5% to 18.9 trillion won from

the same period a year earlier.

"We expect to see solid refining margins in the second

quarter backed by continued cuts by OPEC+ and improved travel

demand," SK Innovation said in a statement.

The refiner said it plans to carry out maintenance work for

its No.4 crude distillation unit (CDU) in the second quarter.

Analysts say rising oil prices benefited the company's

petrochemical business, helping to offset losses from its

battery unit SK On, which has been facing weaker electric

vehicle (EV) battery demand.

SK On, which supplies to Ford Motor Co ( F ), Volkswagen

and Hyundai Motor ( HYMTF ) among others, widened

its operating loss to 332 billion won in the first quarter from

18.6 billion won in the previous quarter due to fewer EV battery

shipments.

SK On's major automaker customer Ford earlier this month

said it delayed the planned launches of three-row EVs in Canada

and its next-generation electric pickup truck built in

Tennessee. Ford executives have said they will not launch the

next generation of EVs until its EV business is profitable.

Analysts noted that SK On, which currently produces only

pouch-type battery cells, should broaden its product lineup to

better meet the needs of automakers which are diversifying the

adoption of EV battery types to lower costs.

"SK On needs to secure new clients to make maximum use of

its existing capacity as its current clients are struggling with

weaker EV sales," said Cho Hyunryul, an anlyst at Samsung

Securities.

Last week, SK On's cross-town rival LG Energy Solution

said it planned to minimise capital expenditure this

year due to slowing global EV demand, after reporting a 75% drop

in quarterly profit.

Shares in SK Innovation were trading up 1.6%, versus the

benchmark KOSPI's 0.4% rise as of 0022 GMT.

($1 = 1,376.4300 won)