Bettinelli has praised manager Enzo Maresca and his staff for the way they've been building team spirit this summer.
He wrote for chelseafc.com: "The role of being third or fourth choice goalkeeper in a squad has definitely grown in importance. Before it used to be the position of a young lad but in recent years it seems more clubs are going with the older goalkeeper in that role.
"You still need to be a really good goalkeeper to be able to train and keep up with the standards. You can be a great person but first and foremost you still have to be able to train at the level expected and perform in the way the head coach wants you to.
"When you are third in line, you still need to be ready to step in if there are a couple of injuries. But after that, you have to be a good person, be fair and try to help all the lads.
"So it is important to have all those attributes and it is definitely a growing position in football.
"When I look at this squad, Reece and I were talking the other day and we were saying it definitely feels like this is the closest the group has felt over the last couple of years.
"We have experienced some really tough times over the last two years, some really bad moments, and I think we had a good season last season, we finished well and now the new head coach has come in and we are all really enjoying his ideas and the way he wants us to play.
"The closer we are off the pitch, it is only going to transcend on the pitch and both Reece and I were saying this feels like the closest and the most family-like it has felt over the last couple of years.
"We are definitely building something and I think you are starting to see that on the pitch. Pre-season results are not always the be-all and end-all and the head coach has been saying the whole time that this is about the process and the plan."