Copied from 0.16 update news post:
On a completely other area, an all new game mode has been added to StarMade. Because PvP in sandbox is always connected to time consuming rebuilding, fleeing ships, and other things that don't allow for quick simple fun, battle mode was created. Essentially, an admin can either run this mode on top of sandbox, or dedicate the server to the mode.
Dedicated means, that players will spawn in a personal sector that has its own unlimited shop. They can't leave that sector though.
This is how battlemode works:
1. A countdown will run down. Players can press k to look up the current status and leaderboards.
2. To enter a battle, the players have to join the battle factions defined by the admin. Those factions will always be open to join from the faction hub menu. Logged out players are automatically removed
3. Depending on what faction configuration have the most players, an FFA (if more players are in the FFA faction), or team battle (if more players are in the team factions) will start
4. upon start, all players are warped into battle in that ship they are currently in. A copy of that ship will remain in the personal sector. You can also warp into battle as an astronaut
5. Before the battle starts, the ships can neither fire nor move, except the astronauts, so they have time to man a turret of a teammate
6. The battle itself is deathmatch or team deathmatch at the moment, but more modes will come.
7. After the match, the players are brought back to their sectors where they can make changes to improve their fighters.
Admins can also define the map that is used in the battle secor by simply exporting a sector and setting that name in the config.
All the necessary options are in the server config. Please do not turn on personal sectors on existing sandbox servers as it might jail players (the sector mode to not be able to enter/exit can be set with admin commands).