Can I use my MacBook Pro without battery

It will run at half speed if the battery is not installed. Having the battery sitting on a shelf is not going to make it last any longer. In fact it might shorten it's life. Batteries need to be used regularly.

Half the speed. If it has a 2.8 GHz processor it will run at 1.4 GHz if the battery is not installed. Leave the battery in and use it on battery periodically. The battery is there to be used and will last the longest when it is used regularly. What good is a battery with a low cycle count that won't hold a charge? That's what you will end up with if you don't use the battery.

If I will be using my battery everyday then I will be eating at least 3-4 battery cycles per day.

There aren't enough hours in the day to drain and recharge your battery three times, let alone four, even if you work constantly around the clock and never sleep. And if you're always close enough to a power outlet to recharge your battery the moment it runs down, there's no reason ever to unplug the AC adapter except to give your battery a little light exercise every couple of days and calibrate it every two or three months. It sounds as though you have some major misconceptions about your battery and how to use it. Read this article carefully for everything you'll ever need to know about the battery:

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