New line in a cell with more than 255 characters

[duanyukai]

I've found this tricky way to insert new line in a cell with excel4node.
ws.cell(1, 1).formula('="first line"&CHAR(10)&"second line"');
But when the cell has more than 255 characters, the cell content disappeared.
Though I can split the text and use CONCATENATE, but is there an more elegant way to insert a long piece of text with new line?