I. Determining the Cause of Leakage: Manufacturing Defects vs. Human Factors
The primary criterion for determining whether a leak in an energy storage liquid cooling plate is covered by warranty is the cause of the leak. Industry statistics indicate that the main causes include welding micro-cracks and porosity (manufacturing defects), material fatigue, aging or degradation of seals (O-rings, gaskets), and stress from thermal cycling and vibration—with gasket degradation accounting for approximately 42%, vibration fatigue for 31%, and corrosion for 19%.
Leaks resulting from such manufacturing or material defects fall within the scope of the quality warranty, and manufacturers are required to provide free replacements. Conversely, leaks caused by improper installation or removal, unauthorized modifications, the use of non-original parts, external impacts or drops, failure to follow operating instructions, or use in extreme environments are explicitly excluded from warranty coverage.
Once a liquid cooling plate leaks, coolant seepage into the battery module can directly lead to short circuits and thermal runaway; industry data shows that cooling system failures account for about 17% of accidents involving energy storage containers, with an average repair cost of approximately $18,000 per leakage incident.
Therefore, establishing liability is a prerequisite for any warranty claim.
II. Warranty Period and Scope of Coverage
The warranty period for energy storage liquid cooling plates and associated components varies based on the classification of the complete system.
Taking mainstream all-in-one energy storage cabinets as an example, the Power Conversion System (PCS) inside the cabinet typically carries a 5-year warranty, while air conditioning or liquid cooling units are covered for 3 years.
For liquid cooling products sold separately, manufacturers generally offer a 3- to 6-year warranty with a “replacement-only” policy, providing a free replacement of the same model for leaks caused by quality issues rather than human error.
Liability for consequential damage caused by leakage is a critical issue: if leakage resulting from inherent product quality defects (excluding human error) damages associated hardware, manufacturers typically include this in their compensation coverage. For instance, manufacturers of liquid cooling products often compensate for damage to battery modules or cells caused by leakage based on a sliding scale—100% in the first year, 85% in the second, and 75% in the third (or via physical hardware replacement)—while some offer “full compensation for leakage” over multiple years.
For energy storage applications, it is advisable to clearly specify the following in procurement contracts: the warranty period for liquid cooling plates and units; the scope of liability for consequential damage from leakage (including coverage for damaged cells/modules); compensation ratios and caps;
and whether the warranty for replacement parts extends the original warranty or continues based on the remaining term.
III. Leakage Detection and Evidence
Determining whether a liquid cooling plate leak falls within the warranty scope requires testing and evidence gathering.
Common industry practices include: visual inspections (observing coolant color to locate leaks; checking weld points for leaks, cracks, or extensive corrosion; and verifying that quick-connect valve cores spring back correctly); pressure testing (pressurizing the system with deionized water—e.g., to 1.2 bar—for approximately 15 minutes and monitoring for excessive pressure drop); and specialized tests for seals and welds (such as compression set measurements, thermal imaging scans, and ultrasonic or dye-penetrant testing to detect hidden weld defects).
According to the group standard T/CASMES 421-2024, energy storage liquid cooling systems should be inspected every 3 to 6 months. Inspection items include checks for leakage (in cooling lines, cold plates, and connections) and weld integrity, as well as valve operation and coolant analysis (pH 7.0–9.0; chloride content ≤25 mg/kg; ethylene glycol concentration ~50%; and electrical conductivity ≤10 µS/cm). When filing a warranty claim, manufacturers may require the unit to be returned to the factory for testing;
therefore, obtaining a return authorization and retaining photos of the leakage site and operational records is essential.
IV. Warranty Exclusions
Based on the terms of various manufacturers, warranty exclusions regarding leaks in energy storage liquid cooling plates can be categorized into eight types: 1. Improper handling by the user—incorrect installation or removal, impact or dropping, unauthorized modification, or use of non-original parts; 2. Improper usage—failure to follow the instruction manual, use in extreme environments, or application for purposes other than those intended; 3. Failure to perform required maintenance—neglecting periodic inspections and fluid replenishment, or introducing contaminants during maintenance; 4. Damage during transport or handling—claims must be filed with the carrier; 5. Improper coolant usage—mixing coolants of different brands or specifications, or failure to replenish fluid in a timely manner; 6. Force majeure—natural disasters such as fire, flood, lightning, or earthquake; 7. Missing identification information—loss, damage, or alteration of serial numbers or warranty labels; and 8. Expired warranty or third-party repair—claims made after the warranty period has expired or following unauthorized repairs.
Additionally, if no actual leakage fault is found or if testing results in an NDF (No Fault Found) determination, the original unit will be returned, and the party requesting the repair shall bear the shipping costs.
Energy storage project contracts should clearly specify these exclusions to avoid future disputes.
V. Recommendations for Procurement and Maintenance
To ensure the warranty for energy storage liquid cooling plate leaks is effectively honored, four key points should be addressed: First, prioritize manufacturing processes and testing capabilities when selecting a supplier—favor those using automated laser welding, maintaining a batch yield rate above 99.8%, and producing welds capable of withstanding 10 MPa of pressure that pass both helium leak testing and 24-hour static pressure retention tests (industry data shows leakage rates for traditional argon arc welding can reach 18%, while brazing involves complex processes with high leakage risks; process quality directly determines leakage probability). Second, secure warranty and consequential damage coverage in the contract—clearly define the 3-year warranty for the liquid cooling unit and specify the duration, percentage, and maximum limit for compensation regarding battery components damaged by leaks. Third, adhere to maintenance standards—inspect for leaks, weld integrity, valves, and coolant status every 3 to 6 months; in the event of a leak, cut off power and disconnect fluid lines before replacing the leaking component or quick-connect fitting, then run a test cycle of at least 4 hours after maintenance and retain records for at least one year. Fourth, implement immediate shutdown protocols upon detecting a leak—cut power immediately, take photos for evidence, and report the issue within 24 hours;
avoid disassembly while powered or unauthorized dismantling to prevent voiding the warranty due to human error.
For liquid cooling plates requiring multiple repairs within 12 months, frequent coolant replacement, or showing visible surface corrosion exceeding 15%, consider full plate replacement rather than repeated repairs.
Conclusion
Are leaks in energy storage liquid cooling plates covered by warranty?
The answer is: leaks caused by manufacturing defects—such as microscopic welding cracks, material fatigue, or seal aging—are covered under warranty, allowing for component replacement and compensation for consequential damage to other parts; however, leaks resulting from improper installation or disassembly, unauthorized modification, external force, or improper maintenance are not covered.
By selecting superior manufacturing processes, clearly defining warranty and consequential damage terms, and maintaining a 3-to-6-month inspection and documentation schedule, you ensure that if a leak occurs in the liquid cooling plate—the “thermal management lifeline” of the energy storage system—there is a valid basis for claims and compensation.
