Battery
| Battery | |
|---|---|
| |
| Category: | Power |
| Function: | stores power |
| Fits small grid | |
| Mass: | 1040.4 kg |
| Power: | 4 MW |
| PCU: | 15 |
| Size: | 3x2x3 |
| Time to Build: | 20 sec |
| Fits large grid | |
| Mass: | 3845.0 kg |
| Power: | 12 MW |
| PCU: | 15 |
| Size: | 1x1x1 |
| Time to Build: | 40 sec |
| Data Controls: | [edit] [purge] (?) |
The Battery is a functional block which stores power from Reactors, Solar Panels, Hydrogen Engines, and Wind Turbines for later use. For related smaller block, see Small Battery.
The Warfare Battery style variant has the same functionality and recipe as described here; you need to purchase the Warfare 2 Pack DLC to build it.
Usage
You expected a battery to provide power, but your ship dropped like a rock? You expected the batteries to recharge after docking, but they didn't? Check your settings in the Control Panel Screen.
Tip: Add the battery block's Recharge On/Off and Discharge On/Off actions to your Cockpit toolbar. The icon will display their status: Auto, Charge, or Drain.
How to charge/discharge batteries
Open the Control Panel Screen to change the block's Charge Mode.
- Automatic: The battery charges itself if there is excess power on the ship, and discharges (provides power) if a block needs it.
- This is the recommended default.
- Choose Automatic if your ship has several batteries to charge from Wind/Solar/Reactor or from a base.
- Recharge: The battery actively draws power from other power sources including other batteries. The battery stops providing power.
- Use Recharge to drain another battery before dismantling it. Transfer of power between batteries is lossy!
- While recharging, make sure you're safely docked, because batteries on Recharge will not provide energy to thrusters.
- Enable Recharge to build up charge from Solar/Wind/Reactors in a backup battery.
- Discharge: The battery provides power to other blocks and stops trying to recharge itself.
- Use this to drain a battery that you want to leave behind or dismantle.
- If there are several batteries on one ship, toggle Discharge to Auto to prevent them from drawing power from each other (which is lossy).
Is the battery charging/draining?
The number how many of the four indicator lights are lit and unlit represents the charge percentage in steps of 25%.
- If the indicators are green, the battery is providing power.
- If the indicators are orange, it is drawing power to recharge itself and not powering any other blocks.
- If the indicators are blue, it is powering other blocks by discharging (draining) itself.
Power
When providing power, batteries are given medium priority. Grids draw power first from 
Solar Panels and 
Wind Turbines, then second from batteries. Reactors are only used if the output of the higher priority options is not sufficient, in order to conserve their uranium fuel.
Large grid battery:
- Max output: 12 MW
- Max input: 12 MW
- Max stored power: 3 MWh
Small grid battery:
- Max output: 4 MW
- Max input: 4 MW
- Max stored power: 1 MWh
Note: In Creative Mode, a battery has infinite stored charge, but still limited throughput (input/output)! If a grid exceeds its maximum power usage, you still need to add several batteries, even in Creative Mode.
Comparisons
Weight Comparison
When providing power, batteries are more efficient in terms of mass than Small Reactors on small ships, but they're only 80% as efficient as reactors in terms of power generated per volume in comparison.
However, in contrast to reactors and hydrogen engines, batteries have the advantage of not requiring a conveyor system to feed them fuel, and as such, they can be fitted in spaces not connected to conveyor systems, or be used for short trips, possibly equaling or even surpassing the power density of a conveyored reactor when used in large banks.
A fully discharged battery is just dead weight until it can be recharged using another power source. This means that large banks of batteries are suboptimal for long distance travel. If the battery is only needed to power a drone or shuttle for 15 minutes or less, the battery's life (and power per weight ratio) is sufficient and you can disregard the dead weight issue.
On small grid, seven Small Batteries weigh as much as 1 standard Battery, while offering only one third of the throughput. If you have enough space, replace these seven by a standard Battery.
Efficiency Comparison
Renewable power-producing blocks (solar panels, wind turbines) are the most efficient for recharging batteries. Given that each kilogram of Uranium ingots generates 1 MWh of power in a reactor, one full charge on a small battery is roughly equal to 0.36 ingots and on a large battery, about 1 ingot. However, recharging batteries with reactors only has a 80% efficiency, meaning you'll need somewhat more uranium to recharge batteries than to fuel a reactor.
Transferring power from one Battery to another is possible, but inefficient (lossy), so only do it in emergencies. For example, it makes sense to transfer the power out of a wreck that you are about to grind down, because it's better to lose 20% than to not salvage the power at all. But don't set up Timer blocks to discharge and recharge batteries in docked ships on the regular.
On small grid, you'd need 20 Small Batteries to get the same throughput as one standard Battery, but they'd have three times the mass and 2 SG blocks larger volume.
Trivia
Batteries are the densest block in game, they have very high mass for their small volume, even before being welded up.
- You cannot give a mobile grid "infinite power" by simply building a wall of batteries, because the increased mass will make it too sluggish. Lower the power needs by building specialised mobile grids instead of a heavy "jack of all trades".
- When a rover has flipped in Survival Mode, there are different approaches to turn it right-side-up again: One is to shift the Center of Mass by building a long temporary stalk of (unwelded!) blocks until the vehicle topples back to the other side, and then grind the stalk off. Unwelded Batteries are the block of choice for this solution.
Construction
If progression is enabled, build a 
Basic Assembler first to unlock it.
Batteries exist for small grids in 3x3x2 small blocks size, which makes them quite unwieldy. On large grids, Batteries take up 1x1x1 large blocks of space. For a tiny variant, see Small Battery.
Batteries can attach to other blocks on any of the six sides. Immediately after construction, the battery is already charged up to 30% of its capacity, ready to be used by other blocks. No "cables" or ports are needed for this block to provide power to the grid!
Some faces of the block display a charge indicator, so when placing it, consider whether you want to rotate the block for these coloured lights to be visible or not. The large-grid battery has a built-in Control Panels on the four sides with indicators, the small-grid variant doesn't.
When grinding down a battery, the 
Power Cell components become 
Scrap Metal; this means you cannot gain infinite power by grinding and rewelding batteries repeatedly -- you "pay" for the free partial charge in Power Cell.
Recipe
The Warfare Battery has the same recipe.
 Battery | ||||
|---|---|---|---|---|
| Component | Large Ship/Station Required | Large Ship/Station Optional | Small Ship Required | Small Ship Optional |
 Steel Plate | 20 | 60 | 5 | 20 |
| Power Cell | 80 | — | 20 | — |
 Construction Comp. | 10 | 20 | 2 | 3 |
 Computer | 25 | — | 2 | — |
