The available capacity of lithium-ion batteries can fall significantly to 50% of the nominal value at low temperatures (-20°C) (e.g., the measured capacity of Tesla 4680 cells drops from 82kWh to 41kWh), and the charging efficiency is lowered by 60% (the total charge duration is extended from 30 minutes to 75 minutes). According to the Norwegian Electric Vehicle Association’s data in 2023, when the ambient temperature in winter is on average -10°C, the attenuation rate of the vehicle’s range is 38%, and the energy consumption of the battery heating system in some models accounts for up to 25% (e.g., Volkswagen ID.4 has an additional 4.2kWh consumption per 100 kilometers). Samsung SDI test data shows that when the operation temperature of batterie is over 60°C, the decomposition rate of electrolyte is 12 times greater, and the thickening rate of the SEI film of the negative electrode is as much as 1.2nm/ cycle (0.1nm/ cycle under normal condition), causing the capacity retention rate to drop suddenly from 95% to 68% after 300 cycles.
The risk of thermal runaway from high temperature rises exponentially. CATL statistics show that the internal short-circuit risk of the ternary lithium batterie at 80°C is 17 times that at 25°C (0.003% to 0.051%), and thermal runaway propagation speed can be 8m/s (0.5m/s at normal temperature). Samsung Note7 battery in the year 2016 had a diaphragm design fault (with a temperature resistance degree of only 130°C vs. Industry standard of 150° C. When ambient temperature exceeds 40°C, expansion pressure exceeds 20MPa (safe limit 15MPa), causing 35 burning accidents worldwide. The UL 1642 standard in the United States requires the battery cell to not explode for 2 hours when subjected to a 150°C hot chamber test, while the median failure time for a poor quality battery cell is just 43 minutes.
Differences in material technology determine the tolerance limit. The capacity retention rate of lithium iron phosphate (LFP) batteries at -20°C is 65% (48% for ternary lithium), yet their low-temperature charging acceptance current needs to be limited to 0.2C (1C under room temperature). Byd’s Blade battery expands its working temperature range to -30°C to 80°C with a nano-coating (versus standard LFP of -20°C to 60°C), but its cycle life at high temperature is still 40% lower than that at room temperature (2000 to 1200 cycles). Solid-state batterie also performed better in NASA’s extreme testing, still providing 85% of its capacity at -50°C (Toyota prototype data), but it is three times as expensive to produce as conventional batteries ($450 per kWh vs. $150 per KWH).
The performance of the thermal management system has a direct effect on the versatility of batterie. Porsche Taycan’s 800V design, in combination with a liquid cooling system, can control the temperature difference of the battery cells within ±2°C (±15°C for the air cooling system), which increases the peak power output maintenance rate in a -30°C environment from 45% to 82%. 2024 BMW i7 PTC heater power is as much as 9.6kW, which has the capability to rise the battery temperature to 10°C within 30 minutes at -20°C (12% of the energy use), but at the cost of 7% of the driving range. Argonne Lab testing in the US proves that battery packs with phase change materials (PCM) can reduce temperature rise rate by 62% (from 0.8°C/min to 0.3°C/min) at a high ambient temperature of 40°C but increase system mass by 19% (from 450kg to 535kg).
Economic cost vs. lifespan is a very important trade-off. According to the BloombergNEF report, to ensure the stable operation of batterie within a range of -40°C to 85°C, there is a need to incorporate an additional 23% cost to BMS (approximately 420 per vehicle). Besides, the thermal management energy use (adding 58/kWh to the whole vehicle’s total cost of ownership (TCO)) can expand the 80°C cycle life of the battery cells from 500 times to 1,200 times, and the investment return rate (ROI) is 1:4.3.
Extreme conditions challenge the technical boundaries: In 2021, the BYD batterie energy storage system of the Antarctic research team was still running on diesel heating at -55°C, and the energy storage operating cost per kWh was 12 (0.3 under room temperature). The 2170 battery used in SpaceX Starships controls the capacity attenuation rate at 0.01% per time through multi-layer aerogel insulation in the alternating -180°C to +127°C lunar surface environment. However, the weight of one battery system is 1.2 tons (with only 110Wh/kg energy density). EU BATTERY 2030+ program requires the next-generation batterie to provide a capacity efficiency of > 80% across the entire range of -50°C to 100° C. Currently, the compliance rate is only 7% (23 of the 300 models in the test samples passed).