v3.26.1
Cover - shares
 6 Months Ended
Jun. 30, 2026
Aug. 03, 2026
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2026  
Document Transition Report false  
Entity File Number 001-39291  
Entity Registrant Name EOS ENERGY ENTERPRISES, INC.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 84-4290188  
Entity Address, Address Line One Two Allegheny Center Nova Tower 2  
Entity Address, City or Town Pittsburgh  
Entity Address, State or Province PA  
Entity Address, Postal Zip Code 15212  
City Area Code 732  
Local Phone Number 225-8400  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding (in shares)   364,167,744
Entity Central Index Key 0001805077  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Document Fiscal Period Focus Q2  
Document Fiscal Year Focus 2026  
Common Stock    
Document Information [Line Items]    
Title of 12(b) Security Common stock, par value $0.0001 per share  
Trading Symbol EOSE  
Security Exchange Name NASDAQ  
Public and private placement warrants    
Document Information [Line Items]    
Title of 12(b) Security Warrant, each whole warrant exercisable to purchase one share of Common Stock at an exercise price of $5.481  
Trading Symbol EOSEW  
Security Exchange Name NASDAQ