Capacity loss by temperature
See how ambient temperature affects usable battery capacity. Lead-acid loses significant capacity in the cold; lithium is far less sensitive but must not charge below freezing.
Lead-acid chemistries lose a significant share of usable capacity as temperature drops, so the same battery delivers less runtime on a cold night than on a warm one. LiFePO4 loses far less capacity to cold but has a hard limit lead-acid doesn't: it must not be charged below freezing without a heater or BMS cutoff, even though it can still discharge safely in the cold.
Related calculators
Looking for a definition or a quick answer? See the solar & battery glossary for terms used on this page, or the FAQ for common sizing questions.
Sources & standards
- IEC 60896 — Stationary Lead-Acid Batteries (test & performance requirements) — International test standard covering VRLA (AGM/gel) and flooded stationary lead-acid batteries.
- IEC 62619 — Safety Requirements for Secondary Lithium Cells and Batteries for Industrial Applications — International safety-testing standard for LiFePO4 and Li-ion (NMC) cells used in stationary storage.
Estimates for planning only. Verify with a meter and follow NEC / local code; have a licensed installer confirm any system before purchase or wiring. See the methodology for formulas and sources.