NEA® 8040 Series Battery Cell Bypass Switch

The NEA® 8040 Series Battery Cell Bypass Switch is an electrically initiated, one-shot switch that provides critical protection to battery assemblies by bypassing and isolating failed battery cells. It consists of a spring-loaded plunger with highly conductive metal plated electrical contacts arranged in a Single-Pole, Double-Throw (SPDT) configuration, ensuring Make-Before-Break functionality after actuation. The plunger is restrained using patented split-spool and bridge wire technology. These switches are typically placed in series between battery cells and, when activated, bypass and isolate failed cells from the battery assembly. The design ensures no contact bounce during high dynamic loads seen during satellite launch. Make-Before-Break functionality prevents voltage dropout during switching, and low switch contact resistance ensures high continuous current carrying capability for reliable system operation. Some models include built-in Zener diodes for autonomous operation, redirecting current through the actuation fuse wire upon detecting a failed cell, which can reduce costs associated with battery cell sensing and switch actuation circuitry. Key features include availability in non-autonomous and autonomous configurations, ability to carry up to 400 A continuous current, high reliability, long service life, low power switch resistance, lightweight design, extended operating temperature range, compatibility with pyrotechnic initiation circuitry, range safety friendliness, and use of space-rated materials. Factory refurbishment is also available.