Hydrogen + Oxygen Battery Gas Calculator

Use the hydrogen gas calculator below to better understand how much gas your system generates.

  • Total Gas Output of Hydrogen (H2) and Oxygen (O2)

  • Change capacity, chage, C-rate, duration, temperature and # of batteries

  • Custom current or quick reference preset Float, Normal or Boost charge

  • Compare with FLUX Vents installed

  • Calculate Lower Explosive Limit (LEL) of 4% Hydrogen concentration

  • Adjust for Ventilation

Flooded Lead Acid Battery (FLA) vs. Flooded Lead Acid Battery + FLUX Vent — H₂ / O₂ Gas Output

Volume
Temp
Include FLUX vents Recommended
Turn on “Include FLUX vents” to select 1–4 per battery.
Calculate Lower Explosive Limit (LEL) OFF
Presets set current = (preset C-rate) × Capacity.
Advanced options OFF
Flooded Lead Acid (No FLUX Vents)
—
— L/min H₂
— L/min O₂
— L/min total
Total Gas Generated (—): — L
Flooded Lead Acid (with FLUX Vents)
—
— L/min H₂
— L/min O₂
— L/min total
Total Gas Generated (—): — L
Reduction in Gas with FLUX Vents
— less H₂
— less total gas
Catalyst capacity used: —
% of Hydrogen (H₂) in Enclosure i Hydrogen volume percentage in the enclosure air. With ventilation, this shows the steady-state value (generation balanced by removal).
Without FLUX: — of air (vol %)
With FLUX: — of air (vol %)
Set ACH/CFM above.
Time to 4% Lower Explosive Limit (LEL) — no ventilation i How long it takes for H₂ to reach 4% (LEL) if there is no ventilation.
Without FLUX: —
With FLUX: —
Assumptions: Ideal gas @ 1 atm; Faraday’s law; “Gas Fraction” drives raw H₂/O₂; FLUX recombination is rate-limited by 1.12 L/min H₂ per vent; results scale by number of batteries.

NOTE: These are engineering estimates for ventilation and hazard assessment based on idealized stoichiometry and user‑provided overcharge assumptions. Actual gas evolution varies with charge regime, SoC, temperature, electrolyte, and hardware. For compliance or hazardous‑location design, consult applicable standards and perform direct measurements.