The time honored term "battery" has come down to us through the years as a traditional baseball term to define the relationship between the pitcher and catcher. A battery in military terms describes a group of artillery pieces which by definition deliver missiles to a target, which is very relevant to a pitcher throwing to a catcher, but I'm going to focus more on the catching aspect of the battery.
If you ask any pitcher, they will tell you that they have a favorite catcher. In the 2 1/2 months I have been in Fort Myers, I have developed a good relationship with 2 of our catchers here. I feel most comfortable throwing with these 2 guys because I am confident they will call and catch a good game. Whenever I know I'm starting I like to check the starting lineup to see who my catcher will be. Without a doubt I do get a little excited when I see the names of my 2 favorite catchers on the lineup card.
Catchers have the tough job of keeping pitchers motivated and emotionally stable while on the mound. They are ultimately responsible for pitcher productivity. The pitching coach can help with advice and encouragement between innings as well, but the catcher and pitcher are the ones who have to do it during the game. It's the catcher who should call the signals. It's the catcher who can call time out, go to the mound, and talk to a wild pitcher without the threat of his pitching being removed from the game. A good catcher will know his pitcher's strengths and weaknesses and will be able to help a struggling pitcher with advice on mechanics or strategy.
Working together, a good battery can deliver its missile on target every time with maximum effect. Teamwork and communication are essential. As a pitcher's and catcher's relationship and trust in each other develop, game strategy discussions should and will become routine. If that confidence is missing, it will be a long season and chances of it being a winning one are slim and none. They must be able to communicate with each other and be able to work together with mutual respect.
When Roy Halladay won the 2010 Cy Young Award for the best pitcher in the National League, he also got an exact replica of the award made for his catcher Carlos Ruiz, who was behind the plate when Roy threw a perfect game and no-hitter. I'm sure the gesture was meant to say "I couldn't have done it without you".