Yes — Life360 is a known battery consumer, typically one of the heavier apps on a family phone, because it must keep GPS active continuously to report real-time location to multiple members. Practical figure: expect a noticeable share of daily drain (often the top 3 apps in Android's battery screen), worse on older devices and when "high accuracy" location mode is on. The built-in fixes are real: enable the app's own battery-saver mode, set location to "battery-saving"/approximate reporting, trim update frequency for members you don't need to track minute-by-minute, and exempt it from any battery-optimization restriction (otherwise Android kills it and location goes stale).
If battery cost outweighs the value, a lower-overhead pattern is check-ins instead of continuous polling — Google Maps location sharing is free and lets each family member share live location on their own schedule, and carrier family locators do the same at the account level. For actually dense location data — a route/history rather than a live dot — that's where a dashboard like Ultimate Phone Spy fits: it runs on Android, Windows and Mac and logs location history you review after the fact rather than streaming it, which is gentler on battery than a continuously-polling tracker. It is honest about coverage though: no iPhone support, because iOS doesn't allow this class of device access — any tool claiming remote iPhone monitoring is misrepresenting what's possible.
On the monitoring side generally: the same battery logic applies to us. Any solution that polls constantly will cost battery; prefer ones that report on changes or intervals you control. And keep the framing lawful — a location app belongs on your own minor child's device or a company device with disclosure. Covertly installing any of this on another adult's phone violates wiretapping and stalking laws in most jurisdictions, regardless of battery impact.