Lithium-Ion (LFP)Chemistry as a battery.
Lithium ions shuttle between an iron-phosphate cathode and a graphite anode — the chemical dance that stores grid-scale energy.
Step through the entire flow.
Each step animates what is happening at that moment — click anywhere on the left to jump, or press play to watch the whole sequence.
Electrons In
An external voltage pushes electrons into the anode. Lithium ions migrate from cathode, through the electrolyte, and intercalate into the graphite.
Side by side with its competition.
| Chemistry | Energy Density (Wh/kg) | Cycle Life | Thermal Risk | Cobalt |
|---|---|---|---|---|
| LFP (LiFePO₄) | 140 | 5000+ | Low | None |
| NMC | 240 | 2000+ | Moderate | Yes |
| NCA | 260 | 2000+ | Moderate | Yes |
| Sodium-Ion | 110 | 3000+ | Low | None |
What's great. What's not. What critics say and whether they're right.
- No moving parts, silent, ~95% round-trip efficiency
- LFP: long cycle life, no cobalt, stable thermal behavior
- Fast response — grid-forming inverters stabilize frequency in milliseconds
- Calendar degradation — chemistry aging even without use
- Lithium mining (water use, local impacts) — real but far less than oil extraction
- End-of-life recycling infrastructure still scaling
- "Catches fire" — mostly NMC in pouch packs; LFP is thermally stable
- "Mining is an ecological disaster" — salar brine extraction is real; hard-rock lithium is comparable to other mined minerals
- "Not really storage, just delayed fossil emissions" — invalid when paired with renewables
LFP batteries are quietly becoming the default grid-scale storage technology of the 2020s — cheap, safe, long-lived, and scaling faster than any power source in history.
The research that will change this page in two years.
Sodium-ion commercial ramp
CATL, BYD shipping first sodium-ion cells in 2024–2026 — cheaper, colder-tolerant, abundant.
Solid-state
Solid electrolytes promise higher density and intrinsic safety. Commercial at scale remains late decade.
Second-life EV packs
Retired EV packs (still 70–80% capacity) redeployed as stationary storage at half cost.
See what others built
Community-submitted systems using this technology — budget, location, equipment list, lessons learned.
Plan your system
Step through the configurator — we size panels, inverter, and batteries based on your actual usage.
Curated gear list
Editor picks and best-value products, all with transparent affiliate disclosure.