Battery capacity
The capacity of the device's own battery (see "Power source").
The general purpose of the battery depends primarily on this indicator. If the recorder uses a relatively modest battery, up to 500 mAh, this most often means that it plays the role of a backup power supply in case of disconnection from the cigarette lighter (for example, in an accident when the on-board mains fails). In such cases, you can not pay special attention to the capacity - it is usually guaranteed to last at least a few minutes of autonomous recording, and for continuous operation, the device will still have to be connected to the cigarette lighter. But for full (not "spare") power, much more capacious batteries are required - at least 800 mAh, and ideally 1000 mAh and higher. The exception is ultra-compact motorcycle models that do not have screens and do not consume much energy - for them, 200 mAh or even less is sometimes enough.
It should be noted that, theoretically, a more capacious battery allows the device to work longer without recharging. However, in practice, comparing different models by this indicator essentially makes no sense: after all, the autonomy of the recorder also depends on its energy consumption, and it is determined by a number of characteristics. Moreover, manufacturers sometimes select batteries of different capacities for different models precisely with the calculation to achieve more or less the same operating time on a charge.