You expand your battery in Tears of the Kingdom by trading Crystallized Charges to a Steward Construct at a Crystal Refinery. Each upgrade costs 100 Crystallized Charges and buys you one energy well, and three wells make one full battery segment. That price is flat: the hundredth upgrade costs exactly what the first one did.
Where the Crystal Refineries Are
There are two, and the first is easy to miss because it appears while you are still learning the game:
- Great Sky Island, near Nachoyah Shrine.
- Hyrule surface, between Lookout Landing and the Hyrule Castle Town Ruins.
The surface one is the one you will use for the rest of the game. It is close enough to Lookout Landing to fold into your normal travel.
What the Upgrade Actually Buys
The unit the game trades in is the energy well, not the full battery. Three wells equal one complete battery segment, so a full new segment is 300 Crystallized Charges. Going from the starting battery to the maximum takes 45 upgrades, which works out to 4,500 Crystallized Charges in total.
That number is worth sitting with before you start. Maxing the battery is a long project, not an afternoon.
Where Crystallized Charges Come From
The main sources are Zonaite, which you refine into charges, and the Zonaite you pull out of the Depths. The Depths are by far the richer source, and any serious battery expansion effectively means spending real time down there.
Large Zonaite gives considerably more than the small variety, so mining deposits properly rather than grabbing surface scraps changes your rate substantially.
What to Do With Charges Once You Are Maxed
Charges keep their value after your battery is full. The Steward Construct stocks ten of each Zonai device, and almost all of them cost three Crystallized Charges each. Big Batteries are the exception at 30 charges apiece.
So a maxed battery does not make your Zonaite worthless. It converts your mining into a device supply instead, which matters a great deal if you build vehicles. Our guides on shield surfing and throwing items cover the traversal and combat tricks that pair well with a device stockpile.
If you are still working through the main quest, our Master Sword guide covers the other major long-term goal worth planning around.
Frequently Asked Questions
How many Crystallized Charges for one full battery segment? 300, because a segment is three energy wells at 100 charges each.
Does the cost go up as you upgrade? No. It stays at 100 charges per well throughout.
Can you lose battery upgrades? No. Once purchased they are permanent.
Is it faster to farm Zonaite in the Depths or on the surface? The Depths, comfortably. Surface Zonaite is far more scattered.