DOA bad service
Internal Loosening / Poor Internal Fixturing: Shaking a new battery produces abnormal noises, indicating that the internal cells or the Battery Management System (BMS) are not securely fastened. This poses a potential safety hazard. Exaggerated Specifications / Performance Not Meeting Claims: Measured internal resistance is excessively high. Actual capacity does not meet the rated capacity. In extreme cases, batteries arrive dead (0V), rendering them immediately unusable (DOA - Dead On Arrival). BMS (Battery Management System) Malfunction / Firmware Issues: Specifically in models like the 12V 314Ah, common problems include: Parallel Connection Asynchronization: Batteries do not balance or work together correctly when connected in parallel. SOC (State of Charge) Display Fluctuation/Jumping: The battery's reported charge percentage is unstable or inaccurate.