The large number of batteries in the energy storage system, large capacity and power, dense arrangement of batteries, and complex and variable working conditions are prone to problems such as uneven temperature distribution and large temperature difference between batteries, which lead to degradation of battery performance, capacity reduction and shortened service life, affecting the performance of the whole system, and in serious cases, may lead to thermal runaway and safety accidents. In order to realize the energy storage to large-scale, medium-long cycle, strong tolerance and high safety performance direction, liquid cooling technology has become a popular route in the field of thermal management of energy storage.
Currently, in the market the mainstream thermal management methods, which would be shown as below.
Air cooling
Air cooling is a kind of cooling method using air as cold medium and convection heat transfer to reduce the temperature of the battery, which is widely used in industrial refrigeration, telecommunication base station and data center temperature control scenarios, with relatively high technical maturity and reliability.
Liquid cooling
Liquid cooling is a kind of liquid as a refrigerant, using liquid flow to transfer the heat generated by the internal components of the IT equipment in the data center to the outside of the equipment. Compared with air cooling, the structure of the liquid cooling system is more complex and compact, and it does not require the deployment of a large area of heat dissipation channels, so it occupies a relatively small area.
Heat pipe cooling
Heat pipe cooling relies on the phase change of the cooling medium enclosed in the tube to realize heat transfer, with high heat dissipation efficiency, safety and reliability, etc., but the cost is also high, and the practical application in large-capacity battery systems such as energy storage is relatively small.
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Three main heat management technical routine comparison |
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Characteristic |
Air cooling |
Liquid cooling |
Phase change cooing |
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Cooling medium |
Air |
Liquid |
Phase change material |
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Contact method |
Directly |
Indirectly |
Directly |
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Design |
Easy |
Complex |
Easy |
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Heat transfer efficiency |
Lower |
Higher(0.5-10) |
Medium |
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Cost |
Lower |
Higher |
Medium |
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Protection |
Low requirements, easy to achieve |
Complex system,hard to achieve |
Simple system, easy to achieve |
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Heat transfer coefficient |
25-100 |
1000-15,000 |
/ |
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Temperature uniformity |
Non uniformity |
Uniformity |
Uniformity |
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Lifespan |
≥10 years |
3-5 years |
Related with materials |
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Installation |
Easy |
Difficult |
Easy |
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Application |
Low battery energy density, recharge and discharge |
High battery energy density, recharge and discharge |
Medium |
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Technical maturity level |
Mature |
Mature |
Immature |
Due to the higher heat transfer coefficient and specific heat capacity of the coolant and the fact that it is not affected by factors such as altitude and air pressure, the liquid cooling system has a stronger heat dissipation capacity than the air-cooled system, which is more adaptable to the development trend of large-scale, high-energy-density energy storage projects.
From the cost point of view, according to the relevant research, in the case of the same cooling effect, liquid cooling system energy consumption is usually much lower than air-cooled system. Therefore, although the initial investment cost of liquid cooling system is higher, its comprehensive cost in the whole life cycle of the energy storage system may be lower than that of air-cooled system. In summary, we believe that in some scenarios, liquid cooling is expected to gradually replace air cooling as the mainstream form of temperature control for energy storage.
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The advantages of liquid cooling |
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Low energy costs |
Liquid cooling can utilize 45°C/113F water for cooling most of the time |
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High cooling power density |
Air cooling for cabinets over 20kW significantly reduces the effect of chip-level liquid cooling and immersion. |
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Low Water Consumption |
Evaporative cooling can be eliminated or significantly reduced |
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Adaptation to harsh environments |
Submerged liquid cooling does not require any airflow and is isolated from the external environment. |
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Low noise level |
Chip-level liquid cooling requires only a small amount of airflow |
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Uniform heat dissipation |
Good average heat dissipation for energy storage and power batteries. |
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Significantly lower energy consumption |
Overall power consumption is low, under the same refrigeration capacity conditions, the power consumption is only as low as that of air-cooled units. |
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Year-round effects are sustainable |
Less affected by weather, less seasonal volatility |
The scale of liquid cooling market
Liquid cooling technology has been recognized by some downstream end-use enterprises.
In August 2023, Longyuan Power Group released the second batch of framework procurement of liquid cooling system and pre-assembled converter-booster integrated cabin for energy storage power stations in 2023, and the procurement estimate of liquid cooling energy storage system was 600MW/1200MWh; National Energy Group released the second batch of framework procurement bidding notice of energy storage equipment in 2023, and the total amount of liquid cooling battery system for energy storage power stations was 600MW/1200MWh.
And since 2022, relevant manufacturers have intensively launched liquid-cooled energy storage systems, and the richness of liquid-cooled products has been increasing.
In May 2022, Sunny Power launched PowerTitan for large ground power stations and PowerStack for commercial and industrial energy storage, both of which use liquid-cooled systems.
In the project announced to be put into production by GCL EnerD, the liquid-cooled pack battery pack adopts lithium iron phosphate battery cells, with a maximum cycle life of up to 15,000 times, and at the same time adopts an integrated liquid-cooled piping design, with a temperature difference of less than 3°C. The integrated liquid-cooled energy storage cabinets are categorized into two major series of products, namely, 100kw and 200kw, which can support the demand for all kinds of industrial, commercial and industrial power stations of various sizes and in any combinations, and the prefabricated form can reduce the time and cost of installation and debugging at the site. The prefabricated form can reduce the time and cost of on-site installation and commissioning.
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New liquid cooling energy storage product in 2022 |
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| No. |
Enterprise |
Product name |
Characteristic |
Application |
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Container energy storage system |
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1 |
Kelong |
Kelong S liquid-cooled energy storage system |
Including 1500V energy storage battery, cluster, liquid cooling system, safety protection system and intelligent management system. Safe, Smart and Simple. |
New energy generation side, grid side, user side |
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2 |
Sungrow |
PowerTitan |
Liquid-cooled Energy Storage Solution |
Large Ground Power Station |
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3 |
Chinaztt |
New Generation MUSE1.0 Liquid Cooling System |
Iron phosphate batteries with ceramic coated building, trace element doping and BMS equalization, aluminum frame with pre-violet structural modules: IP67 rated battery compartment with independent fire protection system, PACK level monitoring and cluster level spraying design, U-shape liquid-cooling plate and professional piping design. |
/ |
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4 |
Sermatec |
Serlattice liquid-cooled containerized energy storage system |
Liquid-cooled thermal management design with high system integration densityPACK-level fire protection: local security warning system |
Commercial and industrial energy storage |
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5 |
Hyberstrong |
HyperSafe Series Intrinsically Safe Solid State Battery Liquid Cooled Energy Storage System |
It adopts 280Ah iron phosphate solid state battery; it implements technical guarantee in four dimensions of battery safety, integration safety, police safety and active safety, so as to achieve the safety of the whole system. |
/ |
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6 |
Zhougu |
CX-1000 Raw Container Energy Storage System |
With IP54 protection level; C4-5 corrosion protection, modular and highly integrated design of multi-stage fire-fighting system, and prefabricated cabin mounting solution. |
/ |
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7 |
Naradapower |
New generation CenterL liquid-cooled energy storage system |
Liquid-cooled system, loaded with 280Ah iron phosphate batteries 1500V system platform with high efficiency and integration of the ultimate safety and long life, better LCOS four major advantages |
/ |
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8 |
Eve |
Eve 1500V liquid-cooled energy storage system |
With comprehensive protection, accurate temperature control, flexible layout, high efficiency gain four core advantages, support DC1500V voltage platform, rapid deployment, rapid networking |
/ |
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9 |
Ipotisedge |
1500V intelligent liquid-cooled energy storage system |
No installation required, liquid-cooled design, dual fire protection, intelligent cloud, real-time analysis, ten-year life span, lifetime operation and maintenance |
Renewable Energy Grid Integration, Grid Ancillary Services, Grid Transmission and Distribution Distributed and Microgrids |
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10 |
Chintpower |
New Generation PowerBlock Energy Storage System |
Highly integrated energy storage battery module, high voltage box, temperature control system, early warning fire system, power distribution system, etc. |
Large-scale energy storage plants |
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11 |
Trinasolar |
Liquid Cooled Energy Storage Cabinet Products TrinaStorageEle menta |
With “cost-effective, ultimate safety, intelligent operation and maintenance of convenient and flexible” four major advantages |
/ |
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12 |
Hithium |
New generation liquid cooled container |
Adopt side cooling technology, optimize system temperature distribution through multi-stage variable diameter thermal management system design; multiple electrical protection design; system safety using exhaust channel explosion relief and fire extinguishing system design |
Grid side, power side |
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13 |
Shuangdeng Group |
Shuangdeng PowerBank New Liquid-Cooled Energy Storage System |
Multi-dimensional fire-fighting and pre-assembled design of the complete system with liquid-cooling technology |
Large-scale energy storage plants |
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All in one energy storage cabinet |
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1 |
Sungrow |
PowerStack |
Liquid-cooled energy storage solution for “triple power integration |
Commercial and industrial power plants |
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2 |
Teplore |
TensorpackT Distributed Energy Storage System |
Adopting highly integrated design concept, the cabinet integrates battery, BMS EMS, thermal management system, DC/AC bi-directional converter and fire-fighting system into one. |
Industrial and commercial scenarios such as factory parks, charging stations, commercial buildings, data centers, etc. |
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3
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Sermatec |
Liquid-cooled integrated outdoor cabinets |
Highly integrated PCS, battery, liquid cooler, power distribution and fire protection system: wide voltage input paradigm, maximum support for 4 parallel units: 3-layer BMS architecture, digitalized LCD display, loaded with intelligent EMS, to achieve the related equipment data acquisition and monitoring. |
/ |
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4 |
Sinexcel |
Battery Storage Outdoor Cabinet |
Small industrial and commercial users to 30kW energy storage transmitter as the core. Support multiple cabinets in parallel, to meet the megawatt level of medium and large industrial and commercial communities, islands and other fields recorded in the grid, off-grid, weak grid scenarios, plug and play, integrated All-in-one design. |
Small commercial and industrial users |
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5 |
Hyberstrong |
New generation of HyperSafe series liquid-cooled storage cabinets for intrinsically safe solid-state batteries |
Utilizes 280Ah potassium iron phosphate solid state battery; implements technical safeguards in the four dimensions of battery safety, generation safety, management safety and active safety to achieve the safety of the entire system. |
Household energy storage, energy storage power station, commercial and industrial energy storage |
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6 |
Jd-energy |
Modular Liquid Cooler Source Grid Side 1500V Energy Block eBlock372 |
Al-in-one design, the battery, BMS, high PCS, safety system, thermal management system into a single standardized outdoor cabinet, forming an integrated, plug-and-play energy block energy storage system integration products industrial and commercial power plants |
source network side |
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7 |
Commercial and Industrial Customer Side 1000V Energy Block Products eBlock200 |
/ |
Commercial and industrial user side |
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High Voltage Cascade Energy Storage System |
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1 |
Jinpan Technology |
Fully liquid-cooled 35kV/12.5MW/25 MWh High Voltage Cascade Storage |
No transformer required, direct access to high voltage above 6KV. Grid: using battery active equalization technology, high-voltage cascade energy storage technology and all-liquid cooling thermal management technology. |
Generation side, grid side, industrial and commercial user side |
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2 |
Zhiguang |
Cascade type 35kV high voltage direct mounted large capacity energy storage system |
Jointly developed by Zhiguang Energy Storage, Huaneng Qingneng Energy Academy and Shanghai Jiaotong University, it is suitable for the construction of new energy storage power plants and large-scale GW-level electrochemical energy storage power plants. |
Large-scale energy storage plants |
At present, including domestic and foreign mainstream energy storage integration manufacturers have basically launched the liquid-cooled thermal management technology-based energy storage equipment, and from the second half of last year, in many projects gradually carried out a wide range of applications, some manufacturers have even given up the air-cooled energy storage products, the full push of liquid-cooled technology route. Therefore, compared with the air-cooled system, with the liquid-cooled system technology and application scenarios continue to mature, it is more able to meet the urgent needs of the market for energy storage system scale and energy density is increasing in high energy density, low footprint, low auxiliary energy consumption and fine temperature control advantages will attract more attention.
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Energy storage temperature control equipment companies |
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Enterprise |
Main clients and process |
Main product |
Technical routine |
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Envicool |
CATL, BYD, Narada Power, KeLu Electronics, PingGao Group, Sunshine Power, Hyberstrong, as well as foreign MC series of power outdoor cabinet air conditioner, MC series of mainstream system integrators and battery manufacturers; 2021 energy storage storage air conditioner, EMW series of energy storage chiller temperature control business revenues amounted to 337 million yuan |
C series mainstream system integrators and battery manufacturers; 2021 energy storage storage air conditioner, EMW series energy storage chiller |
Air cooling, liquid cooling |
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Shenling |
State Grid, etc. |
Integral roof-mounted air conditioner, split column room air conditioner, integral embedded air conditioner, room-mounted split precision air conditioner |
Air cooling |
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Tongfei |
In 2020, the company began to lay out the temperature control field of energy storage, and expanded its customers to include Sunny Power, Kelong, Trinasolar, etc. |
Liquid-cooled systems, roof-mounted industrial air conditioners, integrated industrial air conditioners, split industrial air conditioners, wall-mounted air conditioners |
Air cooling, liquid cooling |
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Gaolan |
Our main customers are distributed battery integration manufacturers and battery factories, and we have already started cooperation with Ningde Times. |
Based on the lithium battery single cabinet energy storage liquid cooling products large-scale energy storage power station liquid cooling system, prefabricated cabin energy storage liquid cooling products, etc. |
Liquid cooling |
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Songzhi |
It has entered the supplier system of Ningde Times, Vision Energy and other customers, with two products entering the mass production stage and several products under development. |
Liquid-cooled thermal management system for energy storage (two products in mass production, several in development) |
Air cooling, liquid cooling |
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Aotecar |
Supply to Ningde Times will start in 2020, and the bottom batch production of liquid-cooled thermal management system for energy storage will start in 2021. |
Energy Storage Liquid Cooling and Thermal Management System |
Air cooling, liquid cooling |
The potential of liquid cooling energy in the future
In terms of cost, according to relevant studies, the energy consumption of liquid cooling systems is usually much lower than that of air-cooled systems, given the same cooling effect. Therefore, although the initial investment cost of liquid cooling system is higher, its comprehensive cost in the whole life cycle of energy storage system may be lower than that of air-cooled system. In summary, we believe that in some scenarios, liquid cooling is expected to gradually replace air cooling as the mainstream form of temperature control for energy storage.
In spite of this, liquid cooling systems still face certain challenges in terms of reliability. Previously, the application of liquid cooling in the field of energy storage temperature control is relatively small, the maturity of the technology than the air-cooled still have a certain gap, especially in the stability and reliability of operation. Specifically, liquid cooling system piping is prone to corrosion and deposition, resulting in blockage or leakage of coolant, while water, glycol, silicone oil and other common coolants may damage the battery or cause system short-circuiting, resulting in energy storage power station safety risks.
In addition, the design life of the energy storage system usually reaches 15 years, but the service life of the pumps and valves inside the liquid cooling system is often about 7 years, and there is a certain mismatch between the two. Therefore, it is very likely that the liquid cooling system will need to be maintained or the components replaced by shutting down the liquid cooling system in the course of the operation of the storage project, which affects the economy of the project. Of course, with the progress of liquid cooling technology, we believe that these problems are expected to be solved one after another, the overall view of liquid cooling will still be the future development trend of energy storage temperature control.
