Industries
Explosion protection in the battery industry
The battery industry works with two very different chemistries, and each brings a different kind of explosion hazard. With lead-acid batteries, charging generates hydrogen — gas group IIC, the strictest of all. In lithium-ion production, electrolyte solvents appear at electrode coating and drying, and cells can release flammable gases when they fail, during thermal runaway. The documentation has to keep the zones of both chemistries current.
Industry experience
Sound familiar?
Hydrogen is released in the lead-acid battery charging room, but the classification does not treat it as gas group IIC.
An electrode dryer runs with solvent vapour, but the LEL monitoring and the zone classification are out of date.
Gas can be generated during cell formation or testing, but the documentation does not assess it.
A new production line or warehouse is brought into service, but the zone classification does not follow the change.
Ahead of an audit you spend days gathering the zone drawings, the equipment list and the inspection certificates.
Hazards
Typical explosion hazards in the battery industry
In this industry the hazard depends on the chemistry, so the classification has to treat lead-acid and lithium-ion technology separately:
| Hazard source | Where typical | Typical zone |
|---|---|---|
| Hydrogen (IIC) | lead-acid battery charging rooms, formation | gas zone (1/2), IIC |
| Electrolyte solvents | electrode coating and drying, cell manufacturing | gas zone (1/2) |
| Thermal runaway gases | cell formation, testing, storage | gas zone, critical on failure |
| Electrode and active material dust | mixing, coating, cutting | dust zone (21/22) |
| Electrostatic charging | drying, dust handling, filling | an ignition source in every zone |
Charging lead-acid batteries generates hydrogen continuously, and hydrogen falls into gas group IIC, so charging rooms have to be designed for the strictest protection and adequate ventilation. In lithium-ion production, electrode coating and drying release solvent vapour, and the dryers run with LEL monitoring. Thermal runaway is the characteristic risk of lithium cells: on failure a cell can release flammable gases and heat, which needs attention in manufacturing, in testing and in storage alike. Handling electrode active materials can also bring a dust hazard.
When we help
Typical situations when it’s worth talking
Two chemistries, two explosion hazards
What distinguishes the battery industry is that lead-acid and lithium-ion technology present quite different hazards, and often sit together on one site:
Lead-acid batteries generate hydrogen. Charging produces hydrogen of gas group IIC; the ventilation and classification of the charging room are critical.
Lithium-ion production works with solvents. Electrode coating and drying release flammable solvent vapour, in dryers managed with LEL monitoring.
Thermal runaway produces flammable gases. Cells can release gas and heat on failure; this has to be taken into account in manufacturing, in testing and in storage.
The two chemistries have to be handled separately. Hydrogen zones and solvent zones call for different classifications and different equipment.
The solution
How EPDS helps in the battery industry
EPDS brings explosion protection documentation into one system, from the charging room to cell manufacturing:
Zone and equipment register in one place.
EPDS records the hydrogen, solvent and dust zones, and every Ex device with its marking, gas group and location.
Lead-acid and lithium-ion handled separately.
The software tracks the zones of the two chemistries apart from each other, so they cannot get mixed up.
Management of change.
The software traces the effect of a new production line, chemistry or warehouse through the zones and the protective measures.
No more overdue inspections.
The system gives notice of inspections as they fall due, and records the ones completed.
An audit-ready report in one click.
EPDS assembles the report of zones, equipment and inspections, per site too.
Documentation that is always current.
You can look back at any time to see who changed what, and when.
Knowledge hub
Before you decide, get informed.
Our expert knowledge base explains the concepts of explosion protection clearly.
FAQ
Frequently asked questions
Why is hydrogen gas group IIC with lead-acid batteries?
Charging lead-acid batteries generates hydrogen continuously, and hydrogen falls into the strictest gas group, IIC. The charging room therefore has to be designed for IIC-rated equipment and adequate ventilation.
What explosion hazards come with lithium-ion production?
Electrode coating and drying release flammable solvent vapour, and cells can give off flammable gases on failure, during thermal runaway. These have to be assessed in manufacturing, in testing and in storage.
What is thermal runaway, and how does it affect explosion protection?
Thermal runaway is the self-sustaining overheating of a lithium cell, during which the cell releases flammable gas and heat. It presents both an explosion and a fire risk, so the classification and the risk assessment both have to cover it.
When does the zone classification have to be redone?
At every change that affects the explosion hazard: a new production line, a different chemistry, a new warehouse, or a modification to the ventilation or the process. In EPDS this is part of management of change.
Does a battery plant need explosion protection documentation?
Yes. Wherever a flammable gas, vapour or dust can create an explosive atmosphere, the documentation is mandatory under decree 3/2003. (III. 11.), and it has to be kept current.
Let’s talk it through — free consultation
In a short, free conversation we show you the EPDS system mapped onto your processes, and review where your documentation stands today.