Aziz Bench

Battery comparison: which chemistry to choose

Tick what your project needs and see which of 15 battery chemistries fit, best first, with every figure side by side: voltage, energy, cycles, current, cold-weather charging, fire risk and shipping. Each figure comes from a named datasheet.

Best match
LiFePO4
3.2 V · 109–163 Wh/kg · 1,000–6,000 cycles
Matching chemistries
11 of 15
Requirements
1
Energy per kilogram
109–163 Wh/kg
Requirements met by each chemistry
LiFePO41/1Li-ion1/1NiMH LSD1/1LiPo1/1LTO1/1AGM1/1Li-SOCl₂0/1Lithium AA0/1Alkaline0/1Gel1/1Sodium-ion1/1CR20320/1NiMH standard1/1Flooded1/1Supercapacitor1/1

Recommended for your project

The chemistries that have everything you ticked, best first.

RechargeableBest match

LiFePO4

3.2 V · 109–163 Wh/kg · 1,000–6,000 cycles

The long-life lithium choice: thousands of cycles, a flat 3.2 V and a lower fire risk than other lithium-ion cells.

Fits because: rechargeable

Watch out: Heavier than Li-ion for the same energy, and no charging at 0 °C or below. Its flat voltage makes the charge hard to read from the voltage.

Rechargeable

Li-ion (NMC/NCA)

3.6 V · 221–260 Wh/kg · 400 cycles

The most energy per kilogram among rechargeables, in standard 18650 and 21700 cells with high-capacity and high-current versions.

Fits because: rechargeable

Watch out: No charging below 0 °C, and a damaged or shorted cell can catch fire: use protected cells or a BMS.

Rechargeable

NiMH low self-discharge

1.2 V · 84 Wh/kg · 2,100 cycles

An AA or AAA you can recharge up to 2,100 times that still holds 70 % after 10 years in a drawer.

Fits because: rechargeable

Watch out: 1.2 V instead of 1.5 V: a few devices show a low battery early. Panasonic advises against devices with airtight battery compartments.

Type and format
Performance
Conditions, safety and shipping
Compare two chemistries

The full side-by-side table is just below ↓

Chemistries that match (11)

  • LiFePO4rechargeable
  • Li-ion (NMC/NCA)rechargeable
  • NiMH low self-dischargerechargeable
  • LiPo (pouch)rechargeable
  • LTO (lithium titanate)rechargeable
  • Lead-acid AGMrechargeable
  • Lead-acid gelrechargeable
  • Sodium-ionrechargeable
  • NiMH standardrechargeable
  • Flooded lead-acidrechargeable
  • Supercapacitorrechargeable

One requirement short

  • Li-SOCl₂lacks recharging
  • Lithium AA (Li-FeS₂)lacks recharging
  • Alkalinelacks recharging
  • CR2032 coin celllacks recharging

Not confirmed: a figure is missing (0)

  • None.

Good to know

Tick what your project needs. Figures come from one or two named cells per chemistry, and each cell is checked on its own: the current of a power cell and the cycles of a storage cell don’t add up to one battery.

LiFePO4 vs Li-ion (NMC/NCA)

FeatureLiFePO4Li-ion (NMC/NCA)
Differences (14)
Basics
Nominal voltage3.2 V3.6 V
Voltage range2.5 V (empty) to 3.65 V (full)2.5 V (empty) to 4.2 V (full)
FormatsPrismatic storage cells and cylindrical power cells; 12, 24 and 48 V batteries with a built-in BMS18650 and 21700 cylindrical cells, alone or in packs
Example (source of the figures)EVE LF280K (280 Ah), A123 ANR26650M1-B (2.5 Ah)LG MJ1, Molicel P42A
Energy
Energy per kilogram109–163 Wh/kg221–260 Wh/kg
Energy per litre239–347 Wh/L597–727 Wh/L
Life and storage
Cycle life6,000 to 80 % of the energy (EVE LF280K storage cell, 0.5P, 25 °C); over 1,000 at 20 A and full depth (A123 power cell)400 to 80 % (LG MJ1); not stated for the Molicel P42A
Self-discharge and storageAt most 5 % in 28 days at 25 °C (EVE retention test); store at 30–40 %At most 10 % in 30 days at 25 °C (LG MJ1 test)
Current
Maximum continuous dischargeFrom 1C (EVE LF280K storage cell: 1P) to 20C (A123 ANR26650M1-B power cell: 50 A)From 10 A (2.9C, LG MJ1) to 45 A (10.7C, Molicel P42A)
Temperature
Charging temperature0–60 °C · EVE LF280K; full power only around 25 °C: 3 % of it at 0 °C, 30 % at 10 °C (constant-power table); not stated for the A123 cell0–45 °C
Discharge temperaturefrom −30 to 60 °C · EVE LF280K (only 20 % of full power at −20 °C); A123 −30 to 55 °Cfrom −40 to 60 °C · LG MJ1 from −20 °C
Safety, charging and shipping
Fire riskLower than NCA Li-ion and similar to LTO: in 18650 abuse tests thermal runaway began at 234 °C and peaked at 310 °C, against 207 °C and 579 °C for NCA, with the lowest pressure peak of the threeHigher: NCA cells went into thermal runaway at 207 °C and peaked at 579 °C in 18650 abuse tests; a short or an overcharge can start a fire
ChargingCC/CV to 3.65 V per cell at most; a BMS balances the cells and blocks charging in the coldCC/CV to 4.20 V per cell, never above; packs need a BMS
Uses
Typical usesHouse batteries for campers and boats, solar storage, 12 V lead-acid replacements, e-bikes, power stationsPower tools, e-bikes, laptops, flashlights, ESP32 projects on 18650 cells
Same on both (2)
Basics
TypeRechargeable
Safety, charging and shipping
Air transportLithium-ion dangerous goods (UN3480/3481): loose batteries by cargo aircraft only, at 30 % charge at most; since 2026, batteries over 2.7 Wh packed with equipment must also be at 30 % at most. Passengers carry spares in the cabin, up to 100 Wh freely and 100–160 Wh with airline approval; since 27 March 2026, at most two power banks each, not recharged on board

All chemistries side by side

Basics5
FeatureLiFePO4Li-ion (NMC/NCA)LiPo (pouch)LTO (lithium titanate)Sodium-ionLead-acid AGMLead-acid gelFlooded lead-acidNiMH low self-dischargeNiMH standardAlkalineLithium AA (Li-FeS₂)Li-SOCl₂CR2032 coin cellSupercapacitor
TypeRechargeableRechargeableRechargeableRechargeableRechargeableRechargeableRechargeableRechargeableRechargeableRechargeableSingle use (primary)Single use (primary)Single use (primary)Single use (primary)Rechargeable (capacitor)
Nominal voltage3.2 V3.6 V3.7 V2.3 V3 V2 V per cell (12 V = 6 cells)2 V per cell (12 V = 6 cells)2 V per cell (6 V = 3 cells)1.2 V1.2 V1.5 V1.5 V3.6 V3 V2.7 V rated
Voltage range2.5 V (empty) to 3.65 V (full)2.5 V (empty) to 4.2 V (full)2.75 V (empty) to 4.2 V (full)Not stated for single cells1.5 V (empty) to 4 V (full)1.75 V per cell at cut-off; absorption 14.2–14.6 V for 12 V (Victron)1.75 V per cell at cut-off; absorption 14.1–14.4 V for 12 V (Victron)1.75 V per cell at cut-off; absorption 7.40 V for 6 V at 25 °C (Trojan)0.9 V (empty) to 1.4 V (full)0.9 V (empty) to 1.4 V (full)1.5 V nominal; Energizer’s tests stop at 0.8 V1.5 V nominal; Energizer rates the capacity down to 1.0 V3.67 V open circuit; capacity rated down to 2.0 V (Saft)3 V nominal; 235 mAh at 0.4 mA (Renata)0 to 2.7 V: the voltage falls in a straight line as it discharges
FormatsPrismatic storage cells and cylindrical power cells; 12, 24 and 48 V batteries with a built-in BMS18650 and 21700 cylindrical cells, alone or in packsFlat pouch cells; RC and drone packs from 1S to 6S with balance leadsPrismatic cells (Toshiba SCiB 2.9–23 Ah) and modulesCylindrical cells such as the 32140 (10 Ah)12 V blocks; sealed, valve-regulated (VRLA)12 V blocks; sealed (VRLA), with the acid in a gel6 V and 12 V batteries with vents and caps for topping upAA and AAAAA and AAAAA, AAA, C, D and 9 VAA and AAAAA size (14500) and other sizes, often with solder tagsCoin cell, 20 × 3.2 mmCells from a few farads to 3,000 F, and modules
Example (source of the figures)EVE LF280K (280 Ah), A123 ANR26650M1-B (2.5 Ah)LG MJ1, Molicel P42AEEMB LP503759, Grepow 25CToshiba SCiB 20 Ah, 23 AhParagonage 32140 (10 Ah)Victron AGM 12 V 90 AhVictron gel 12 V 90 AhTrojan T-105 (6 V, 225 Ah)Panasonic eneloop AAEnergizer NH15-2300 (AA)Energizer E91 (AA)Energizer L91 (AA)Saft LS14500Renata CR2032Maxwell BCAP3000 (3000 F)
Energy2
FeatureLiFePO4Li-ion (NMC/NCA)LiPo (pouch)LTO (lithium titanate)Sodium-ionLead-acid AGMLead-acid gelFlooded lead-acidNiMH low self-dischargeNiMH standardAlkalineLithium AA (Li-FeS₂)Li-SOCl₂CR2032 coin cellSupercapacitor
Energy per kilogram109–163 Wh/kg221–260 Wh/kg173–185 Wh/kg84–96 Wh/kg111 Wh/kg40 Wh/kg41.5 Wh/kg48 Wh/kg84 Wh/kg102 Wh/kgNo single figure: the capacity depends strongly on the load (Energizer gives it as a chart)≈ 310 Wh/kg≈ 560 Wh/kg≈ 250 Wh/kg6.9 Wh/kg
Energy per litre239–347 Wh/L597–727 Wh/L361–388 Wh/L176–202 Wh/L248 Wh/L101 Wh/L101 Wh/L101 Wh/L273 Wh/L333 Wh/LNo single figure: the capacity depends strongly on the load (Energizer gives it as a chart)≈ 563 Wh/L≈ 1,100 Wh/L≈ 700 Wh/LNot stated in our sources
Life and storage2
FeatureLiFePO4Li-ion (NMC/NCA)LiPo (pouch)LTO (lithium titanate)Sodium-ionLead-acid AGMLead-acid gelFlooded lead-acidNiMH low self-dischargeNiMH standardAlkalineLithium AA (Li-FeS₂)Li-SOCl₂CR2032 coin cellSupercapacitor
Cycle life6,000 to 80 % of the energy (EVE LF280K storage cell, 0.5P, 25 °C); over 1,000 at 20 A and full depth (A123 power cell)400 to 80 % (LG MJ1); not stated for the Molicel P42A500 at 0.5C (EEMB LP503759); not stated for the Grepow cellOver 20,000 to 70 % (Toshiba, 3C, 25 °C)1,500 to 70 % (Paragonage); HiNa reports 96 % after 3,850 cycles in its own test400 at 80 % depth, 600 at 50 %, 1,500 at 30 % (Victron)500 at 80 % depth, 750 at 50 %, 1,800 at 30 % (Victron)1,200 at 50 % depth (Trojan Signature Line)Up to 2,100 (IEC 61951-2:2011); 600 with the 2017 method (Panasonic)Up to 1,000 in ideal conditions (Energizer)Single useSingle useSingle useSingle use1,000,000 (projected at 25 °C, Maxwell)
Self-discharge and storageAt most 5 % in 28 days at 25 °C (EVE retention test); store at 30–40 %At most 10 % in 30 days at 25 °C (LG MJ1 test)No yearly figure: EEMB asks to store at 40–60 % and recharge every 3 monthsNot stated in our sourcesNo yearly figure: the maker asks to store at about 50 % and recharge every 6 monthsUnder 2 % a month at 20 °C, doubling with every 10 °C more (Victron)Under 2 % a month at 20 °C, doubling with every 10 °C more (Victron)5–15 % a month, depending on temperature (Trojan)70 % left after 10 years at 20 °C (Panasonic estimate)50–80 % left after 6 months (Energizer)Shelf life 10 years at 21 °C (Energizer E91; 12 years on the newer E91 Max sheet)Shelf life 25 years at 21 °C (Energizer)Under 1 % a year at 20 °C (Saft)Under 1 % a year at 23 °C (Renata)Leakage 2.8 mA after 72 h at 2.7 V (Maxwell): about 0.08 V a day from full, if the leakage stayed that high (our estimate)
Current1
FeatureLiFePO4Li-ion (NMC/NCA)LiPo (pouch)LTO (lithium titanate)Sodium-ionLead-acid AGMLead-acid gelFlooded lead-acidNiMH low self-dischargeNiMH standardAlkalineLithium AA (Li-FeS₂)Li-SOCl₂CR2032 coin cellSupercapacitor
Maximum continuous dischargeFrom 1C (EVE LF280K storage cell: 1P) to 20C (A123 ANR26650M1-B power cell: 50 A)From 10 A (2.9C, LG MJ1) to 45 A (10.7C, Molicel P42A)From 2C (EEMB LP503759) to 25C (Grepow GRP5934096: 45 A)No continuous figure for single cells; 1,900 W for 10 s on the 20 Ah-HP cell (Toshiba)5C (50 A) between 15 and 45 °C, 0.5C below 15 °C (Paragonage)No continuous figure; 8C for 5 s at most (Victron)No continuous figure; 7C for 5 s at most (Victron)Not stated in our sourcesNot stated in our sources4C at most (Energizer)No rated maximum; internal resistance 150–300 mΩ when fresh (Energizer)2.5 A, 4 A in 2 s pulses (Energizer L91)50 mA, 250 mA in pulses (Saft LS14500)3 mA (Renata); Energizer’s pulse test draws about 6.8 mA for 2 s170 A, 2,300 A peak (Maxwell BCAP3000)
Temperature2
FeatureLiFePO4Li-ion (NMC/NCA)LiPo (pouch)LTO (lithium titanate)Sodium-ionLead-acid AGMLead-acid gelFlooded lead-acidNiMH low self-dischargeNiMH standardAlkalineLithium AA (Li-FeS₂)Li-SOCl₂CR2032 coin cellSupercapacitor
Charging temperature0–60 °C · EVE LF280K; full power only around 25 °C: 3 % of it at 0 °C, 30 % at 10 °C (constant-power table); not stated for the A123 cell0–45 °C0–45 °C · EEMB LP503759; not stated for the Grepow cellfrom −30 to 45 °C · Toshiba: repeated charging and discharging possible at −30 °C; modules −30 to 45 °C0–45 °C · only 0.2C between 0 and 15 °Cfrom −15 to 50 °C · with temperature compensation; 0–40 °C without (Fullriver); never when frozenNot stated in our sources · temperature compensation needed below 10 °C (Victron)Not stated in our sources · Trojan’s operating range is −20 to 45 °C; below 0 °C keep it above 60 % charge0–40 °C · fast charge (Panasonic BK-3MCC)0–50 °CNot rechargeableNot rechargeableNot rechargeableNot rechargeablefrom −40 to 65 °C
Discharge temperaturefrom −30 to 60 °C · EVE LF280K (only 20 % of full power at −20 °C); A123 −30 to 55 °Cfrom −40 to 60 °C · LG MJ1 from −20 °Cfrom −20 to 60 °C · EEMB LP503759; not stated for the Grepow cellfrom −30 to 45 °Cfrom −40 to 60 °C · at least 80 % of the capacity at −20 °C, 60 % at −40 °CNot stated in our sourcesNot stated in our sourcesfrom −20 to 45 °Cfrom −20 to 50 °C · rated for use (Panasonic)0–50 °Cfrom −18 to 55 °Cfrom −40 to 60 °Cfrom −60 to 85 °Cfrom −30 to 70 °Cfrom −40 to 65 °C
Safety, charging and shipping3
FeatureLiFePO4Li-ion (NMC/NCA)LiPo (pouch)LTO (lithium titanate)Sodium-ionLead-acid AGMLead-acid gelFlooded lead-acidNiMH low self-dischargeNiMH standardAlkalineLithium AA (Li-FeS₂)Li-SOCl₂CR2032 coin cellSupercapacitor
Fire riskLower than NCA Li-ion and similar to LTO: in 18650 abuse tests thermal runaway began at 234 °C and peaked at 310 °C, against 207 °C and 579 °C for NCA, with the lowest pressure peak of the threeHigher: NCA cells went into thermal runaway at 207 °C and peaked at 579 °C in 18650 abuse tests; a short or an overcharge can start a fireHigher: the Li-ion chemistry in a soft pouch with no metal case; a swollen, punctured or crashed pack can catch fireLower than NCA Li-ion and similar to LiFePO4: in the 18650 tests runaway began at 233 °C and peaked at 338 °C, with a higher pressure peak than LiFePO4; Toshiba: low risk of fire or explosionNot rated here: we found no independent abuse tests on these cellsNot rated here; sealed (valve-regulated), so there is no acid to top upNot rated here; sealed (valve-regulated), so there is no acid to top upGives off hydrogen while charging: Trojan says never charge it in a sealed or unventilated spaceNot rated hereNot rated hereNot rated hereNot rated hereNot rated hereNot rated here; keep coin cells away from childrenNot rated here
ChargingCC/CV to 3.65 V per cell at most; a BMS balances the cells and blocks charging in the coldCC/CV to 4.20 V per cell, never above; packs need a BMSCC/CV to 4.20 V per cell (LiHV 4.35 V); packs of several cells on a balance charger80 % in 6 minutes in Toshiba’s test; needs a charger and BMS set for LTO voltagesCC/CV to 4.0 V per cell (Paragonage); needs a charger and BMS made for sodium-ion3-stage charger: absorption 14.2–14.6 V, float 13.5–13.8 V for 12 V; temperature compensation below 10 °C and above 30 °C (Victron)Absorption 14.1–14.4 V, float 13.5–13.8 V for 12 V (Victron)Absorption 7.40 V, float 6.60 V, equalize 7.75 V for 6 V at 25 °C, with temperature compensation; top up with water (Trojan)NiMH smart charger (2–3 hours) or 0.1C for 12–14 hours; trickle below C/40 (Energizer)NiMH smart charger (2–3 hours) or 0.1C for 12–14 hours; trickle below C/40 (Energizer)Not rechargeableNot rechargeableNot rechargeableNot rechargeableAny current up to the cell’s limit, stopping at 2.7 V (2.85 V for 1 s at most); cells in series need balancing
Air transportLithium-ion dangerous goods (UN3480/3481): loose batteries by cargo aircraft only, at 30 % charge at most; since 2026, batteries over 2.7 Wh packed with equipment must also be at 30 % at most. Passengers carry spares in the cabin, up to 100 Wh freely and 100–160 Wh with airline approval; since 27 March 2026, at most two power banks each, not recharged on boardLithium-ion dangerous goods (UN3480/3481): loose batteries by cargo aircraft only, at 30 % charge at most; since 2026, batteries over 2.7 Wh packed with equipment must also be at 30 % at most. Passengers carry spares in the cabin, up to 100 Wh freely and 100–160 Wh with airline approval; since 27 March 2026, at most two power banks each, not recharged on boardLithium-ion dangerous goods (UN3480/3481): loose batteries by cargo aircraft only, at 30 % charge at most; since 2026, batteries over 2.7 Wh packed with equipment must also be at 30 % at most. Passengers carry spares in the cabin, up to 100 Wh freely and 100–160 Wh with airline approval; since 27 March 2026, at most two power banks each, not recharged on boardLithium-ion dangerous goods (UN3480/3481): loose batteries by cargo aircraft only, at 30 % charge at most; since 2026, batteries over 2.7 Wh packed with equipment must also be at 30 % at most. Passengers carry spares in the cabin, up to 100 Wh freely and 100–160 Wh with airline approval; since 27 March 2026, at most two power banks each, not recharged on boardSodium-ion dangerous goods (UN3551/3552) since 2025: loose batteries by cargo aircraft only, at 30 % charge at mostNon-spillable (UN2800): not restricted when it passes the spill tests of special provision A67 and the terminals are protectedNon-spillable (UN2800): not restricted when it passes the spill tests of special provision A67 and the terminals are protectedSpillable (UN2794): regulated dangerous goods, in acid-proof packagingNot restricted by air when the terminals are protected against short circuits (IATA special provisions A199 for NiMH, A123 for dry cells)Not restricted by air when the terminals are protected against short circuits (IATA special provisions A199 for NiMH, A123 for dry cells)Not restricted by air when the terminals are protected against short circuits (IATA special provisions A199 for NiMH, A123 for dry cells)Lithium-metal dangerous goods (UN3090/3091): loose cells by cargo aircraft only; passengers may carry cells with up to 2 g of lithiumLithium-metal dangerous goods (UN3090/3091): loose cells by cargo aircraft only; passengers may carry cells with up to 2 g of lithiumLithium-metal dangerous goods (UN3090/3091): loose cells by cargo aircraft only; passengers may carry cells with up to 2 g of lithiumUN3499: cells storing under 10 Wh are not dangerous goods (Maxwell)
Uses1
FeatureLiFePO4Li-ion (NMC/NCA)LiPo (pouch)LTO (lithium titanate)Sodium-ionLead-acid AGMLead-acid gelFlooded lead-acidNiMH low self-dischargeNiMH standardAlkalineLithium AA (Li-FeS₂)Li-SOCl₂CR2032 coin cellSupercapacitor
Typical usesHouse batteries for campers and boats, solar storage, 12 V lead-acid replacements, e-bikes, power stationsPower tools, e-bikes, laptops, flashlights, ESP32 projects on 18650 cellsDrones, RC models, thin devices, wearablesBuses, industrial vehicles, grid storage, solar in cold climatesStationary storage and packs that must work in the coldLeisure and backup batteries, UPS, alarm systems, starter batteriesSlow, regular deep discharges: solar, mobility aidsGolf carts, floor machines, off-grid banks with regular maintenanceRemotes, toys, game controllers, camera flashes, wireless keyboardsHigh-drain devices used every dayClocks, remotes, low-drain devicesOutdoor sensors, trail cameras, GPS units, flashlights in the coldSensors that run for years: meters, LoRaWAN nodes, alarms, trackersReal-time clocks, BLE beacons, remotes, small sensors that sleep most of the timeCurrent bursts and backup: real-time clocks, short power cuts, engine starting, energy recovery

Tap a group to open or close it. Figures come from one or two named cells or batteries per chemistry (the “Example” row), from the makers’ datasheets; where we cite a storage cell and a power cell, or an energy cell and a high-current cell, the table gives the range and names each one. Other products of the same chemistry differ. ≈: worked out by us from capacity × nominal voltage ÷ weight or volume, for single-use cells whose usable energy depends on the load.

Head-to-head comparisons

How to choose

Start from what can’t change: rechargeable or single use, and the format your device takes (AA, a 12 V block, a pouch that fits the case). Then weigh what matters most: weight, cycles, current, cold or years on a shelf. The tool ranks the chemistries that meet everything you ticked and, when none does, shows the closest ones and what they lack.

Rechargeable or single use

Rechargeable cells pay off when you replace batteries often: an eneloop AA is rated up to 2,100 cycles. Single-use cells win when a device must run untouched for years: a Saft LS14500 loses under 1 % a year and an Energizer L91 is rated for 25 years on the shelf.

Energy, cycles and current

Li-ion holds the most energy per kilogram among rechargeables (221–260 Wh/kg in our examples) but lasts about 400 deep cycles. LiFePO4 stores less (109–163 Wh/kg) and lasts 6,000 cycles in a storage cell, over 1,000 in a power cell. LTO goes beyond 20,000 cycles at under 100 Wh/kg. For current, look at the continuous rating of the cell you will buy, not at the chemistry: LiFePO4 goes from 1C in a storage cell to 20C in a power cell, LiPo packs for drones reach 25C, and a CR2032 gives 3 mA.

Cold weather

Li-ion, LiPo and LiFePO4 must not be charged below 0 °C: their datasheets start at 0 °C, and in EVE’s constant-power table the LiFePO4 cell takes only 3 % of its full charging power at 0 °C. LTO can be charged at −30 °C (Toshiba), AGM down to −15 °C with temperature compensation (Fullriver), NiMH from 0 °C (Panasonic, Energizer). For use in the cold, Li-SOCl₂ works down to −60 °C and the Energizer L91 down to −40 °C.

Fire risk

In abuse tests on 18650 cells heated by 5 °C a minute, NCA Li-ion vented at 157 °C, went into thermal runaway at 207 °C and peaked at 579 °C. LiFePO4 and LTO behaved alike: venting at 197 and 187 °C, runaway at 234 and 233 °C, peaks of 310 and 338 °C, with a far lower pressure peak for LiFePO4 (Ubaldi and Russo, 2023). All three released carbon monoxide and hydrogen fluoride above exposure limits. Safer doesn’t mean safe: every lithium cell needs protection against shorts, overcharge and damage.

Shipping and travel

Lithium-ion, lithium-metal and sodium-ion batteries are dangerous goods by air: shipped alone they go by cargo aircraft only, and lithium-ion and sodium-ion at 30 % charge at most; since 2026, lithium-ion batteries over 2.7 Wh packed with equipment must also be at 30 % at most. Passengers carry spare lithium-ion batteries in the cabin, up to 100 Wh without approval, and since 27 March 2026 at most two power banks each, which they may not recharge on board. NiMH and alkaline cells are not restricted when their terminals are protected.

Sources

Datasheets: EVE LF280K, A123 ANR26650M1-B, LG MJ1, Molicel P42A, EEMB LP503759, Grepow GRP5934096, Toshiba SCiB catalogue and 20Ah-HP release, Paragonage 32140 and HiNa NaCR32140, Victron AGM and gel, Fullriver AGM manual, Trojan T-105 and Signature Line sheet, Panasonic eneloop and BK-3MCC, Energizer NiMH handbook, NH15-2300, E91, L91 and CR2032, Saft LS14500, Renata CR2032, Maxwell BCAP3000, TP5000. Safety: Ubaldi and Russo, Chemical Engineering Transactions 104 (2023). Coin cells: TI, “Coin cells and peak current draw”. Li-SOCl₂ passivation: Qoitech’s test of a stored LS14500. Transport: IATA passenger rules 2026, DGR 66 significant changes and guidance documents, UK CAA power bank rules, UPS battery shipping guide.

Frequently asked questions

Which battery lasts the most cycles?

Among these, LTO (over 20,000 cycles to 70 % in Toshiba’s test) and LiFePO4 (6,000 to 80 % for EVE’s LF280K). Supercapacitors reach a projected million cycles but store very little energy. A Li-ion cell like the LG MJ1 is rated for 400 cycles, and AGM lead-acid for 400 at 80 % depth (Victron).

Can I charge lithium batteries below 0 °C?

Not Li-ion, LiPo or LiFePO4: their datasheets allow charging from 0 °C, and in EVE’s constant-power table the LiFePO4 cell takes only 3 % of its full charging power at 0 °C. LTO cells can be charged at −30 °C (Toshiba), and AGM lead-acid down to −15 °C with temperature compensation (Fullriver).

What battery should I use for a sensor that must run for years?

A primary lithium cell: Li-SOCl₂ (Saft LS14500: under 1 % a year, −60 to 85 °C, 3.6 V) or, for 1.5 V AA devices, Li-FeS₂ (Energizer L91: 25-year shelf life). Check the current: the LS14500 is rated for 50 mA continuous and, after years of storage, its first pulses can sag (passivation), so a radio needs a capacitor for its transmit peaks.

Is LiFePO4 safer than Li-ion?

In abuse tests on 18650 cells, LiFePO4 went into thermal runaway at 234 °C and peaked at 310 °C, against 207 °C and 579 °C for NCA Li-ion (Ubaldi and Russo, 2023); LTO behaved much like LiFePO4. Safer isn’t safe: any lithium cell can burn if crushed, shorted or overcharged, so use a BMS and fuses.

Can I replace a 12 V lead-acid battery with LiFePO4?

Yes, with a 12 V LiFePO4 battery: four cells in series (12.8 V) replace six lead-acid cells. Set the charger to a lithium profile: Victron charges its LiFePO4 batteries at 14.0–14.4 V and floats them at 13.5 V. Don’t charge it below 0 °C.

Why can’t I use a Li-SOCl₂ or 14500 Li-ion cell instead of an AA?

They have the AA size but 3.6–3.7 V instead of 1.5 V, so they can destroy a device made for AA batteries. For a 1.5 V AA, use NiMH, alkaline or Li-FeS₂ (Energizer L91).