The battery is a good indicator of that. Without any power source, you'd have a passive bass and be limited in your tone controls to just cutting frequencies w/o the option of boosting. The fact that yours uses a battery means you have something active in your electronics configuration. It could be both the pickups and the preamp/EQ that are receiving power, or it could just be the preamp/EQ or just the pickups. The term active pickups is often used interchangeably with set ups where the pickups are actually powered and where they're not (meaning only the pramp/EQ section is). I'm not sure in the case of your bass what the situation is, but IME with active electronics for bass, it seems most common that only the preamp/EQ section is powered, while the pickups themselves are passive. Sometimes the signal is simply buffered (not technically a preamp as I understand things), with the only amplification really happening when you boost any of the frequency bands of the EQ. Sometimes the circuit with the EQ will give a significant boost to the whole signal independently of the where the EQ bands are set. In many cases the amount of overall gain added is fixed at a certain level, sometimes it's variable via a trim pot or switch on the circuit board. As I understand the situation though, it's appropriate in common usage to simply refer to the whole EQ circuit as a preamp, whether it's really amplifying, or simply buffering.
If you remove the control plate, presumably on the back of this bass, and maybe even where you have to acces the battery (unless there is a battery box set in the back of the bass as well), you should be able to see a small circuit board in there somewhere. That is the preamp.
I only use slight bass and mid boost and overall level boost. I cut the treble with the onboard tone control. Nothing one couldn't do with a 3 band onboard EQ. Not any major changes. Just gives me a little low end, which I especially need when I use a pick close to the bridge.
