Buying a new battery vs. replacing the entire laptop
If the only issue is a depleted battery, replacing the battery is usually the cheapest way to extend the device's lifespan.
When a battery replacement is sufficient
If the rest of your laptop (processor, RAM, display, keyboard) meets your needs, and the only problem is short battery life due to a worn-out battery — replacing the battery (more details in a separate article about the service) solves this specific problem for a small fraction of the cost of a new device.
How to check if the issue is indeed the battery
The command powercfg /batteryreport will show the actual remaining capacity relative to the nominal capacity — if the figure is significantly lower than expected for the device's age, this confirms battery wear rather than other reasons for short battery life.
When to consider replacing the entire device
If, in addition to the battery, there are other significant limitations (outdated RAM/CPU configuration for your current tasks, worn-out keyboard, cracked casing) — the cumulative cost of several repairs might approach the price of replacing it with a used device of a better configuration.
Our recommendation
Compare the cost of battery replacement with the rest of your current device's specifications — if everything else is satisfactory, this is the most economical way to extend your laptop's lifespan.