FUTURE TECHNOLOGY
dimensions such as cell , pack , BMS , system and cloud computing / Big Data should be combined to minimise burning incidents due to thermal runaway .
( 1 ) Cell material selection : LFP is preferred as its safety is ensured thanks to a high temperature for thermal runaway and a low rate and amount of heat yield .
( 2 ) Cell structure safety design : The mechanical structure is cut off promptly to suppress temperature rise and the coating inhibits thermal runaway .
• Mechanical structure : Components such as the fuse and overcharge safety device ( OSD ) are promptly cut off in case of a short circuit and overcharge to suppress temperature rise and prevent thermal runaway due to chain reactions .
• Functional coating ( chemical protection ): If an internal short circuit occurs and the mechanical structure does not work , the functional coating suppresses the shrinkage of the isolation film to avoid large-scale short circuits .
As the market share of lead-acid batteries decreases rapidly , lithium battery usage is increasing around the globe .
( 3 ) Battery pack safety design : Two-level design in four dimensions ensures battery pack safety .
Examples :
• Laser soldering eliminates the risk of loosening screws .
• Multiple temperature sensors monitor the internal temperature and voltage in real-time .
• Proper clamping ensures structural stability .
• The insulating protection plate safeguards positive and negative terminals .
• The plastic insulating bracket ensures insulation and structural strength between cells .
• The insulation film on the cell surface insulates the cell from external components . ( 4 ) BMS safety design : The three-level
BMS architecture with voltage , current and temperature sampling , equalisation , threshold alarm protection , internal shortcircuit detection algorithm and algorithms for internal temperature estimation and lithium plating ensure that cells will not cause thermal runaway . ( 5 ) System safety design :
• The intelligent battery control system controls the voltage , current and power of each battery to avoid bias current and cross current .
• The cabinet-level fire extinguishing system quickly suppresses thermal runaway for precise , efficient and ecofriendly protection . ( 6 ) AI safety assurance : Key data is uploaded to the cloud for monitoring the battery status in real-time . Horizontal and vertical comparison , database and safety algorithm analysis collaborate to provide monthly and daily safety warnings .
Conclusion
Compared with lead-acid batteries , lithium batteries have inherent advantages such as low requirements on load-bearing capacity , small footprint , high energy density and long cycle life . Lithium batteries will be widely used in data centres when the cost is further reduced . To ensure the safety of lithium batteries , LFP cells are recommended and the designs in dimensions such as pack , BMS and system need to combine . Huawei SmartLi UPS is such a solution with the safest LFP cell that can past several reliability tests and have already large-scale use in different industries . •
INTELLIGENT TECH CHANNELS
INTELLIGENT TECH CHANNELS Issue 34
35