The battery life of a voice-activated recorder determines its lifespan. A larger battery allows for longer recording times. Also, as previously said, the device's voice-activation capability often correlates to lengthier operation times. The length of the recording also differs between devices. Some voice-activated recorders have a recording time of up to 90 hours, while others have less than that. You can select a device with a battery that meets your recording requirements. It is best to acquire a long-lasting one if you need to record for several hours or even days.