The test shows that the new Switch lasted 5 hours and 36 minutes whilst playing The Legend of Zelda. This is with Airplane mode turned on and the Switch running at about 50% of brightness. This is about double the battery life of what the original Switch was capable of.
Nintendo advised that the new model would get 4.5-9 hours of battery life with about 5.5 hours when playing The Legend of Zelda: Breath of the Wild (one of the most battery sucking games). The original Switch would struggle to get three hours when playing Breath of the Wild.