Yes, it is possible for a battery to suddenly appear to be dead. This can have various causes:

1. Incorrect battery level display: Sometimes, the battery indicator on a device can be inaccurate and show an incorrect battery level. This can make it seem like the battery is suddenly dead, even though it still has some charge.

2. Interruption of the power supply: If there is a sudden interruption in the power supply to the device, the battery may no longer charge or the energy may be quickly consumed, causing it to seem like the battery is suddenly dead.

3. Defective battery: A battery can become defective due to aging, damage, or other factors. If a battery is defective, it can lose its charge quickly and make it seem like the battery is suddenly dead.

4. Unused for too long: If a battery is not used for an extended period, it may discharge by itself. This is due to the battery's natural self-discharge process. When you try to use the battery again, it can seem like it is suddenly dead.

If you are dealing with a battery that seems to be suddenly dead, it is advisable to charge the battery according to the manufacturer's instructions. If the problem persists, it may be necessary to replace the battery or seek professional advice.