Every conversion stage between a battery and the grid is a place to lose energy. US11764703B1, granted to Foshan Hechu Energy Technology on September 19, 2023, claims a power-conversion method for an AC-direct grid-connected battery storage system — and "direct" is the operative word.
The CPC tags are conversion-specific: H02M 7/797 (conversion of DC to AC with specific switching arrangements) and H02J 7/02 (charging batteries from AC). The patent describes how to convert between the battery's DC and the grid's AC with a topology that reduces intermediate stages — a more direct path than conventional multi-stage designs.
The grid-efficiency mapping is straightforward arithmetic. A typical grid battery converts DC to AC (and back when charging) through multiple stages, each with conversion losses of a few percent. Cutting a stage raises round-trip efficiency, which directly improves the economics of storage — more of the energy stored comes back out and can be sold.
The patent fences a conversion topology/method, not battery storage and not grid connection generally. Many topologies exist; this claims one that prioritizes directness. Its value depends on whether the efficiency gain justifies any tradeoffs (the direct path may complicate protection or control).
From patent to grid, this is component-level IP with system-level consequences. The deployment story for storage is usually told in capacity and cost-per-kWh, but the conversion topology quietly sets the efficiency, and efficiency sets the returns. A 2023 conversion patent from a specialist manufacturer is the kind of upstream IP — far from the headlines — that actually moves the round-trip-efficiency number on which grid-storage profitability turns.