wGrill uses different voltage as Tiger.
When you use re-chargable battery, you must need a charger.
wGrill just ingrates charger into its ciucuit board.
You do not need separate charger.
iGrill and wGrill are really battery eaters.
2 batteries can power the wGrill for 3 hours.
With built-in charger, you just plug AC/DC adapter, it will power the wGrill and at the same time charge the batteries. If any AC power offer, the battery will be used as backup for 3 hours.