Battery

Lore & Background

In the sprawling industrial landscape of Factorio, power is the lifeblood of every operation. Early on, a single coal-fired power pole can keep a handful of furnaces lit, but as the factory sprawls across the alien terrain, the electrical grid becomes a living, breathing system that must be managed with care. The Battery was designed to be the shock absorber of that system—a small, unassuming box that sits quietly among the humming machinery, its amber casing and blinking status LED the only signs that it is doing its job. Players who have wrestled with solar farms know the Battery's true value. A field of panels can flood the grid with more power than the factory can use at midday, then go completely dark at night. Without storage, that means either idling production or building an oversized, wasteful backup generator. A row of batteries, neatly aligned beside the solar array, turns that problem into a non-issue: charge by day, discharge by night, and the assemblers never even notice the sun has set. The upgrade path to Energy Storage II is a small but satisfying milestone. Doubling both capacity and throughput means fewer units are needed for the same job, freeing up floor space for more production. For many players, the moment they swap out a wall of 5-MJ batteries for a shorter wall of 10-MJ ones is a quiet victory in the endless game of optimization.

In Their Own Story

The night cycle crept in like a slow tide, the sky shifting from pale amber to deep indigo. Across the solar farm, panel after panel dimmed to black, their output ticking down toward zero. But the factory did not slow. Along the eastern wall, a long row of batteries glowed faintly, their small LEDs pulsing a steady green. Each one had been gorged with sunlight hours earlier, and now they fed that stored energy back into the grid in a smooth, unbroken stream. The assemblers kept clicking. The furnaces kept roaring. Somewhere in the control room, the player watched the power graph hold flat through the dark, and for a moment the whole operation felt less like a machine and more like a heartbeat—steady, patient, alive.

Reader's Guide

Function: The Battery stores electrical energy and releases it on demand. It has no fuel input, no crafting output, and no item slots—its only interfaces are electricity input and output connectors. It sits passively on the grid, absorbing up to its maximum input rate and discharging up to its maximum output rate. Throughput: By default, a Battery holds 5 MJ of energy and can accept or deliver up to 5 MW. The Energy Storage II upgrade recipe doubles both figures to 10 MJ and 10 MW. It is unlocked by the Energy Storage technology in the Energy tab of the research menu. Role in production: The Battery is not a production machine itself; it is infrastructure. Its primary job is to decouple generation from consumption. In a solar-powered setup it is the single most important component, bridging the gap between daylight and darkness. It also buffers short power spikes caused by large machines (like electric mining drills or arc furnaces) drawing sudden surges. Stacking and adjacency: Batteries are 1×1 tiles and can be placed in any configuration. They do not need to be adjacent to a power pole to function—any electrical connection to the network is sufficient. Multiple batteries in parallel simply add their capacities and throughput together, so a wall of ten 5-MJ batteries gives you 50 MJ of total storage. There is no adjacency penalty or bonus. Pairing: Place them near solar panel arrays for day/night buffering, or near high-draw machines to absorb transient spikes. They work alongside accumulators (which have lower capacity but faster charge/discharge) to cover both long-duration and short-burst storage needs.

Did You Know?

• A single Battery's 5 MJ capacity is roughly equivalent to 5,000 kilojoules—enough to power a default electric furnace for about 50 seconds at full draw.
• Batteries do not need to be directly adjacent to a power pole; any electrical connection to the shared grid is sufficient for them to charge and discharge.
• The Energy Storage II upgrade is a recipe, not a new technology, meaning you can upgrade existing batteries in place without demolishing and replacing them.
• In a purely solar-powered base, the Battery is the only component that lets you run production during the night cycle without a fossil-fuel backup generator.