Modular Power System Hot-Swappable Battery Expansion

The battery backup system is divided into modular battery modules that can be independently connected in parallel to the DC bus. Each module is a self-contained unit with standardized interfaces, allowing incremental capacity expansion without requiring complete system redesign or additional physical space infrastructure.

The battery modules are designed with universal interfaces and standardized voltage levels (e.g., 48V) that allow them to function both as backup power sources and as expandable capacity units. The same modular architecture serves multiple purposes: providing hold-up time, enabling hot-swapping, and allowing capacity expansion without additional physical infrastructure.

The system transitions from a static, fixed-capacity battery installation to a dynamic, expandable modular system. Users can start with a baseline capacity and incrementally add modules as needs evolve, rather than over-provisioning for worst-case scenarios from the beginning. This dynamic approach optimizes the balance between hold-up time and cost.

Instead of providing full backup capacity for worst-case scenarios from the outset, the system implements partial capacity initially and allows incremental expansion. This avoids the excessive cost of pre-provisioning for rare worst-case events while maintaining adequate backup capability for typical operating conditions.

A voltage matching circuit or impedance matching network is introduced as an intermediary between the incoming battery module and the DC bus. This intermediary component gradually equalizes voltage differences through controlled current limiting, preventing direct surge currents while enabling voltage normalization. The intermediary protects both the incoming and existing batteries during the voltage equalization process.

Before fully connecting a new battery module to the DC bus, a preliminary voltage equalization process is performed. The system first establishes a controlled connection that allows gradual voltage matching between the new module and the bus, preventing surge currents. Only after voltage equality is achieved is the full parallel connection established, ensuring safe integration.

The system maintains continuous power delivery to the load during battery module replacement operations. The modular architecture with parallel connections to the DC bus allows one module to be replaced while others continue supplying power, ensuring uninterrupted useful action. This enables hot-swapping capability where batteries can be replaced without system shutdown.

The battery system is segmented into independent, replaceable modules rather than a monolithic unit. This segmentation allows individual modules to be removed and replaced without affecting the overall system operation. Each module is electrically isolated but functionally integrated through the common DC bus, enabling maintenance and expansion without system downtime.

A controlled intermediary circuit is introduced between the incoming charged battery and the DC bus during hot-swap operations. This intermediary provides voltage matching and current limiting functionality that protects against surge currents even when replacing discharged batteries with charged ones. The intermediary ensures safe voltage equalization regardless of the charge state difference between modules.

Before establishing full parallel connection during a hot-swap operation, a preliminary voltage equalization phase is performed. The system detects the charge state of the incoming battery and adjusts the connection strategy accordingly, using controlled current limiting to safely equalize voltages before full power sharing is established. This preliminary action prevents surge currents even when replacing discharged batteries with fully charged ones.