Ultra-long cycle life
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In the vehicle start-stop system, the cycle life of the battery directly determines the usage cost and reliability. Lithium iron phosphate (LiFePO₄) start-stop batteries, with a cycle life of over 2,000 times (capacity retention rate ≥90%), far outperform the 300 to 500 cycle lives of traditional lead-acid batteries (AGM/EFB), completely resolving the life anxiety in scenarios with frequent charging and discharging. The following analysis is conducted from four dimensions: technical principles, measured data, application scenarios, and economy.
I. Technical Principle: Dual Innovation in Materials and Structure
The lithium iron phosphate cathode material adopts an olivine-type crystal structure, with a PO bond energy as high as 800kJ/mol. The volume change rate during charging and discharging is less than 1% (the expansion rate of lead-acid battery plates is greater than 3%), fundamentally avoiding capacity attenuation caused by electrode material fragmentation.
2. No memory effect and deep discharge capacity
LFP batteries support 100% deep discharge (DOD) and have no memory effect. Even if they are in a partially charged state for a long time (such as frequent short-term discharges during start-stop systems), they will not lose capacity due to sulfation reactions like lead-acid batteries.
3. Intelligent BMS lifespan optimization
The built-in battery management system (BMS) extends the cycle life through the following mechanisms:
Voltage balancing: Control the voltage difference of the battery cells within ≤20mV to prevent overcharging/overdischarging of individual cells.
Temperature compensation: Dynamically adjust the charge and discharge rate, reduce current at high temperatures and heat at low temperatures to minimize material loss under extreme working conditions.
Ii. Measured Data: Performance verification after 2000 cycles
According to the ENOV product specification (NORMAL TEMPERATURE CYCLE test), lithium iron phosphate batteries demonstrate astonishing stability during the normal temperature cycle test:
| Cycle count | capacity retention rate | median voltage (V) |
|---|---|---|
|
1 |
100.00% |
3.192 |
|
500 |
98.03% |
3.212 |
|
1000 |
95.33% |
3.210 |
|
2000 |
90.35% |
3.200 |
|
2500 |
88.61% |
3.197 |
Comparison with AGM batteries:
After 500 cycles, the capacity of the AGM battery is ≤70%, and the sulfation of the plates leads to an increase in internal resistance of >30%.
Under the same number of cycles, the capacity retention rate of lithium iron phosphate batteries is still >90%, and the increase in internal resistance is only 7.63% (see the HIGH TEMPERATURE STORAGE test).
Iii. Application Scenarios: The ultimate solution for high-frequency charging and discharging
1. Urban traffic congestion
The vehicle starts and stops 2,030 times per hour. The traditional AGM battery cycles an average of 1.52 times per day and reaches its lifespan limit (about 500 times) within one year. Lithium iron phosphate batteries can be cycled twice a day on average and can be used continuously for more than three years (2,000 times /2 times/day ≈2.7 years).
2. Hybrid and special vehicles
For high-intensity usage scenarios such as taxis and logistics vehicles, the EN12ST180B model (18Ah) has been tested and shown to still output a cold start current of 1080A (CCA) after 2,000 consecutive deep discharges (2C charge and discharge), meeting the daily start-stop requirement of over 100 times.
3. Energy storage and backup power supply
In recreational vehicles and Marine equipment, lithium batteries support 2,000 uses at 80% deep cycle depth (DOD), while lead-acid batteries only allow for 50% DOD (actual cycle life <800 times).
Iv. Economic Analysis: The full life cycle cost is reduced by 50%
| Project | Lithium iron phosphate battery | Lithium iron phosphate battery |
|---|---|---|
|
The cost of a single purchase |
approximately 2,000 |
approximately 800 |
|
Cycle life |
2000 times (capacity ≥90%) |
500 times (capacity ≤70%) |
|
The average annual replacement frequency |
0.5 times (once every three years) |
2 times (twice every one year) |
|
The total cost over five years (including maintenance) |
2000×1 + 0 yuan =2000 yuan |
800×5 + 500 yuan =4500 yuan |
Conclusion: The comprehensive cost of lithium iron phosphate batteries over five years is only 44% of that of traditional batteries, and there is no need for maintenance expenses such as liquid replenishment and anti-sulfidation.
Conclusion
The extremely long cycle life of lithium iron phosphate start-stop batteries is a comprehensive manifestation of their olivine structure stability, intelligent BMS management and deep discharge capability. From laboratory data to actual working conditions, its overwhelming advantages in terms of cost, reliability and environmental friendliness are accelerating the elimination of traditional lead-acid batteries. For start-stop systems, hybrid and special vehicles that are subject to frequent charging and discharging every day, lithium iron phosphate batteries are not only a choice for technological upgrading, but also an inevitable option to reduce the cost throughout the entire life cycle. With the cost reduction brought about by large-scale production, this technology will become the core support of green transportation.
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START-STOP LITHIUM battery
Enov start-stop battery is designed to provide excellent performance for high-demand start-stop vaehicles. It adopts the third-generation intelligent lithium platform architecture to achieve technological breakthroughs in core indicators such as cycle life, environmental adaptability and energy density. Compared with the traditional lead-acid battery system, the energy efficiency is increased by 210%, the cycle life is extended by 8-10 times, and the monthly self-discharge rate is controlled within 3%. Enov's unique low-temperature battery technology makes a breakthrough in achieving stable output in the whole climate domain from -30℃ to 65℃, maintaining more than 90% of the effective capacity release under extremely cold conditions (-30℃), and maintaining 90% of the capacity in high temperature environments (65℃).
The start-stop battery series products cover the mainstream voltage platform of 12V/24V/48V, and support flexible configuration of LFP (lithium iron phosphate) and NCM (lithium nickel cobalt manganese oxide) dual-material system. All models adopt modular design to support customization of different model specifications. Enuo engineering and technical team to provide full cycle technical service support, if you need, please contact us.
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