Lithium batteries

Lithium batteries used in particulate matter (PM) technology mainly include LCO, NMC, NCA, LFP and LTO chemistries, which trade off energy density, lifetime, cost and fire risk. High‑energy LCO and nickel‑rich NMC/NCA give compact, long‑running handheld or mobile PM instruments but have higher intrinsic fire risk and shorter life, so they need tighter battery management and are less ideal for unattended or densely installed monitors. LFP offers lower energy density but much better thermal stability and longer cycle life, making it a preferred choice for fixed PM stations, solar‑powered sensor nodes and safety‑critical indoor systems. LTO‑based packs are bulkier and costly but provide exceptional cycle life and very low fire risk, fitting niche high‑cycle or harsh‑environment PM deployments. Across all chemistries, dealing with lithium‑battery fires in PM systems focuses on prevention and early detection, robust management electronics, and, if a fire occurs, heavy cooling (typically with water), controlling toxic smoke and particulate emissions, and preventing reignition and contamination of sensitive PM measurement hardware.

Lithium Cobalt Oxide (LCO, LiCoO₂)

LCO was one of the first commercial lithium‑ion chemistries and is still widely used in small consumer devices. Typical uses are in smartphones, cameras, older portable electronics and some legacy handheld PM sensors where very high energy per volume is needed. These are very high energy density, so slim and light., manufacturing and performance in low–moderate current applications well‑understood but they have shorter life cycle (roughly 500–1 000 cycles), Uses cobalt, increasing cost and raising supply‑chain and ethical concerns. Lower intrinsic safety; more prone to thermal runaway than LFP and requires tight voltage and temperature control. Low thermal runaway onset temperatures (around 150 °C) and releases significant oxygen from the cathode during failure, which feeds combustion. In fire, cells can vent flammable gases and eject burning material; direct water streams can spread burning ejecta if cells are rupturing, so large amounts of water applied from a safe distance, cooling and defensive firefighting are recommended.

Lithium Nickel Manganese Cobalt Oxide (NMC, LiNiMnCoO₂)

NMC is a “workhorse” chemistry balancing energy density, power, cost and life, and is very common in EVs and industrial batteries.

Typical uses: electric vehicles, power tools, some higher‑end portable PM instruments that need long runtimes and moderate size, as well as battery‑powered PM sampling pumps.

Advantages:

High energy density, significantly higher than LFP, suitable when runtime and size are critical.

Good power capability and acceptable life (about 1 000–2 000 cycles with proper management).

Flexible formulations (different Ni/Mn/Co ratios) let designers tune energy vs power.

Disadvantages:

Less stable than LFP; nickel‑rich NMC has higher reactivity and more aggressive thermal runaway.

Requires more sophisticated battery management and cooling, increasing system cost and complexity.

Contains cobalt and nickel, raising cost and sustainability concerns.

Fire risk and fire behaviour:

NMC cells can enter thermal runaway at roughly 160–210 °C, significantly below LFP.

When abused, the cathode can release oxygen and flammable decomposition gases; this is why NMC is considered a higher fire risk chemistry than LFP.

Firefighting guidance for NMC packs emphasises rapid cooling (large water application), monitoring for reignition and controlling toxic smoke and fine particulate emissions from burning cells.

Lithium Iron Phosphate (LFP, LiFePO₄)

LFP is increasingly used where safety and long cycle life are more important than maximum energy density.

Typical uses: stationary energy storage, solar systems, industrial UPS, many modern low–mid‑range EVs, and field PM monitoring stations or sensor networks that run from batteries plus solar.

Advantages:

Lower fire risk: very thermally stable cathode with strong P–O bonds; thermal runaway onset is around 270 °C, significantly higher than NMC/LCO.

Long cycle life (roughly 2 000–6 000 cycles), well suited to daily charge/discharge in monitoring networks.

No cobalt; lower material cost and improved sustainability.

Disadvantages:

Lower energy density than NMC, NCA or LCO, so packs are heavier and bulkier for the same capacity.

Lower voltage per cell and slightly reduced performance in very cold environments.

Fire risk and fire behaviour:

LFP has the lowest intrinsic fire risk among the main Li‑ion chemistries; it releases much less oxygen and combustion energy in failure events.

However, large LFP packs still contain significant stored energy and flammable electrolyte, so they can burn and re‑ignite; extended cooling with water and careful post‑incident monitoring remain necessary.

Lithium Nickel Cobalt Aluminum Oxide (NCA, LiNiCoAlO₂)

NCA is similar to NMC but tuned for even higher specific energy and is found in some long‑range EVs.

Typical uses: high‑energy EV battery packs, some specialty industrial systems that demand maximum energy per kilogram.

Advantages:

Very high energy density and strong performance, enabling long driving range or long runtime.

Reasonably long life (about 1 000–2 000 cycles), though generally not as high as LFP or LTO.

Disadvantages:

Safety is less favourable; NCA is considered more reactive than LFP and requires robust thermal management and controls.

High material cost (nickel and cobalt) and more complex production.

Fire risk and fire behaviour:

NCA has fire characteristics broadly similar to nickel‑rich NMC: relatively low thermal runaway onset temperature and substantial oxygen release.

For large EV‑style NCA packs, suppression is challenging; best practice is copious water cooling, stand‑off, and managing toxic gases and particulates.

Lithium Titanate (LTO, Li₄Ti₅O₁₂ anode)

LTO is different: it replaces the usual graphite anode with lithium titanate, which dramatically changes behaviour.

Typical uses: high‑cycle, high‑power industrial systems, fast‑charge transit buses, and some niche environmental monitoring platforms that need extreme cycle life or operate in harsh conditions.

Advantages:

Exceptional cycle life, often up to 20 000 cycles, making it ideal for very frequent charge/discharge cycles.

Very high safety margin: LTO is resistant to lithium plating, supports fast charging, and has excellent low‑temperature and high‑power performance.

Disadvantages:

Lower energy density than NMC, NCA, or even LFP; packs are relatively bulky.

Higher cost per kWh, so usually reserved for specialised applications.

Fire risk and fire behaviour:

Because of the stable anode, LTO packs have significantly reduced risk of internal short‑induced thermal runaway compared with graphite‑anode chemistries.

Failures are still possible (electrolyte is flammable), but overall LTO is among the safest lithium‑ion options.

Summary of chemistries

ChemistryEnergy densityTypical cycle lifeTypical usesIntrinsic fire riskNotes

LCOVery high500–1 000Phones, cameras, some handheld PM sensorsHighCompact but less safe, cobalt‑based

NMCHigh1 000–2 000EVs, tools, industrial PM instrumentsHighBalanced performance, needs tight management

NCAVery high1 000–2 000Long‑range EVsHighHigh energy, more reactive

LFPModerate2 000–6 000ESS, solar, PM stationsLowVery stable, heavier packs

LTO (anode)Low–moderateUp to 20 000High‑cycle industrial systemsVery lowExtreme life and safety, costly

Uses in particulate matter technology

PM technology includes handheld particle counters, wearable exposure monitors, fixed reference stations and factory cleanroom monitoring systems. Lithium batteries are central because they provide high energy density, small size and the ability to support data logging, wireless communication and pumps.

Key roles of lithium batteries in PM technology:

Portable PM monitors: handheld counters and low‑cost optical PM sensors for personal exposure and indoor air quality often use small LCO or NMC‑based packs for compact size and long runtime.

Wearables and sensor nodes: networked PM sensors in urban air‑quality networks or industrial facilities typically combine LFP or NMC packs with solar PV, balancing safety, lifetime and cost.

Fixed reference stations: high‑accuracy PM reference instruments need uninterrupted power; many stations now include LFP‑based battery systems to ride through outages and to buffer solar generation.

Cleanroom PM monitoring in battery factories: particle counters and cleanroom instruments in Li‑ion manufacturing are often powered by facility mains, but backup and mobile carts use lithium batteries so that monitoring continues during power disturbances and maintenance.

From an air‑quality perspective, battery safety directly affects PM: abuse of LIBs can release heavy‑metal‑containing particulate matter and smoke, which itself becomes a pollution source. For example, tests on abused Ni‑rich prismatic cells show airborne particles spanning sub‑micrometre to hundreds‑of‑micrometre sizes, with compositions that drive filter design for capturing battery‑fire emissions.

Advantages and disadvantages for PM use

When selecting a chemistry for PM technology, designers weigh energy density, runtime, safety, lifetime, ambient temperature, and cost.

LCO in PM devices:

Advantages: maximises runtime in a very small form factor; well suited to compact handheld meters that users carry in pockets.

Disadvantages: higher fire risk and shorter life; not ideal for 24/7 unattended monitors in public spaces.

NMC in PM devices:

Advantages: good balance of high capacity, moderate size and acceptable life, supporting higher‑power loads such as pumps, heaters or strong wireless radios in reference‑grade PM analyzers.

Disadvantages: higher intrinsic fire risk than LFP, especially in large packs; needs robust battery management and enclosure design.

LFP in PM devices:

Advantages: excellent safety and long life, fitting fixed and semi‑portable PM stations that operate unattended and often indoors or in urban environments where fire risk must be very low.

Disadvantages: heavier and bulkier packs, which can be a constraint for ultracompact wearables or miniaturised personal exposure devices.

NCA in PM devices:

Advantages: suitable in specialised mobile labs or vehicle‑mounted PM systems where extreme energy density is needed, for example, long‑range mobile monitoring platforms.

Disadvantages: safety margins are tighter; high‑energy NCA packs in confined spaces require advanced fire detection, ventilation and suppression planning.

LTO in PM devices:

Advantages: robust in harsh conditions, very high cycle life for sensor nodes that charge/discharge multiple times per day with solar; very low fire risk.

Disadvantages: lower energy density and higher cost limit use mainly to niche industrial monitoring or critical infrastructure PM systems.

A practical example: a roadside PM sensor node powered by a small solar panel may use an LFP pack, trading some size for safety and long life, while a pocket‑sized occupational exposure monitor may retain NMC or LCO cells to remain compact.

Fire risk by chemistry

Across chemistries, relative fire risk is mostly driven by thermal stability and whether the cathode releases oxygen and high heat in failure.

Approximate ranking of intrinsic fire risk (from highest to lowest):

LCO and high‑Ni NMC/NCA: high energy density and more reactive cathodes; lower thermal runaway onset temperatures around 150–210 °C, significant oxygen release.

Moderate‑Ni NMC: still higher risk than LFP, but slightly improved stability depending on formulation and pack design.

LFP: substantially lower risk; thermal runaway onset ~270 °C, lower oxygen release, lower total combustion energy.

LTO‑based systems: among the lowest fire risk thanks to very stable anode and good resistance to lithium plating; overall hazard dominated by electrolyte rather than electrode materials.

A good battery management system (BMS) and proper mechanical design can reduce incident rates for all chemistries but cannot change the intrinsic stability of the materials.

Dealing with lithium battery fires in PM systems

PM instruments pose some particular challenges: they are often indoors or in cleanrooms, near other sensitive electronics, or distributed in public spaces. Fire strategies therefore focus on prevention, early detection, and safe suppression tailored to chemistry.

Key issues and practices:

Detection and prevention:

Use robust BMS with monitoring of cell voltage, temperature and sometimes pressure or gas to detect early fault conditions and shut down safely.

For devices in cleanrooms or densely packed sensor cabinets, particle and gas sensors can provide early warning of venting before flames appear.

Suppression and control (all chemistries):

For actively burning packs, large quantities of water are widely recommended for cooling and limiting propagation; lithium‑ion batteries are not metallic‑lithium primary cells, so water is generally acceptable and effective at heat removal.

The main challenges are: preventing propagation to adjacent cells (especially in NMC/NCA/LCO packs), managing toxic smoke and fine particulate emissions, and avoiding re‑ignition once the surface fire is out but internal cells remain hot.

Chemistry‑specific points:

LCO/NMC/NCA: higher likelihood of rapid thermal runaway spread across cells, stronger jet‑like flames and larger smoke and PM release; designers often employ firebreaks, spacing and vents to direct ejecta away from people and critical equipment.

LFP: lower probability of thermal runaway propagation and usually less violent events, but large packs can still burn for long periods; passive measures such as compartmentalisation and in‑cabinet gas or aerosol suppression can be effective.

LTO: events are rarer; safety focus is often on system‑level issues (short circuits, external fires) rather than intrinsic cell failure.

For PM technology specifically, one additional consideration is that a battery fire directly contaminates the measurement environment, saturating sensors and depositing particulate residue in sampling lines and optics. After any incident, PM instruments usually require decontamination, re‑calibration, or replacement to ensure reliable future measurements.