Excel is not the way to go for lots of data - no module will give you what you want since the limiting factor is built into Excel itself. I would follow the advice of Ish and output .csv which can be read in many types of software and inform your client what he/she wants isn't possible. Either that or split the data into multiple worksheets.
in reply to Need to generate excel having more than 70,000 records
Here's Microsoft's outline of Excel's specification and limits.
Update: It appears I should have read the fine print, sorry for the dated information.