The Signal Report // ENERGY STORAGE
Energy Storage.
Grid batteries, chemistry, and controls, from someone who helps build the AI that cycles them. All reports →
16 in this beat · page 2 of 2
The Battery That Can't Catch Fire
Lithium-battery safety is mostly about stopping a fire once it starts. A zinc-bromide battery is built from water and salts, so there's nothing to burn, and in June 2026 an independent lab tried to set one alight and couldn't. A materials read on what that intrinsic safety really buys, and the energy density and efficiency it quietly costs.
Read the report → Report 023 · Energy Storage · 2026-07-13 · 6 minThe Battery That Stores Its Energy in a Tank
Every phone and EV welds a battery's power and its capacity into the same cells. A vanadium flow battery pulls them apart, storing energy in two tanks of liquid so it can run for twenty years and barely wear out. In 2026 they're finally shipping to real grids. A materials read on what that decoupling buys, and the three things it costs.
Read the report → Report 017 · Energy Storage · 2026-07-10 · 6 minThe Grid Battery That Rusts on Purpose
Google's new 'world's largest battery' hands back only about half the energy you put in. It's an iron-air battery that stores power by rusting iron on purpose, and on a lithium spec sheet that efficiency would be disqualifying. Why it's the whole point instead.
Read the report → Report 012 · Energy Storage · 2026-07-06 · 6 minWhy Lithium Iron Phosphate Won the Grid
Grid storage standardized on a battery that stores less energy than its rivals, and it wasn't a compromise. LFP now takes 90%+ of new storage. The reason goes down to one stubborn phosphorus-oxygen bond that won't let go of its oxygen. A materials read.
Read the report → Report 011 · Energy Storage · 2026-07-06 · 5 minSodium-Ion Batteries Reach the Grid
In 2026 sodium-ion stopped being "a few years away" and started shipping to real grids, from Peak Energy in the U.S. to CATL in China. What sodium actually trades off versus lithium, why that trade is fine for stationary storage, and which datasheet numbers to hedge.
Read the report → Report 006 · Energy Storage · 2026-07-05 · 5 minWhy Grid Battery Fires Keep Dropping
We've built vastly more grid storage, and the fires got rarer, not more common. The EPRI data shows failure rates fell ~99% since 2018, and that the cells were rarely the problem. A chemistry-and-controls read on what actually made them safer.
Read the report →