Depends on the battery / bike combination. I had a Li battery I could start in near freezing weather after being outside overnight. But a buddy who kept his bike in a garage couldn't start his bike sub 40 degrees. In his case I figured it was more a picky Triumph Daytona 675 than a battery (that bike hates starting in cold weather... ask me how I know lol).
My KTM 690 has a Li batt and its a pain in the ass. Granted, turning over all 650cc's at one time is much harder than spreading the displacement out over a few cylinders, regardless, the thing is picky under 50 degrees. I got it down to turning the ignition on and high beams while gearing up, then low beams and hold the "flash to pass", then it usually cranks no problem.
If I had to buy a battery for my FJ, there's no way it would be a Li. Saving a few pounds is not worth it for this bike (IMO)