Toyota and Mazda have begun field tests of the Sweep Energy Storage System at Mazda's Hiroshima plant, testing the reuse of electrified-vehicle batteries to smooth renewable power and advance a scalable, circular battery ecosystem.

Toyota and Mazda have kicked off field tests of Toyota’s Sweep Energy Storage System at Mazda’s Hiroshima plant, marking a notable step in reusing reclaimed batteries from electrified vehicles to smooth grid power while backing renewables. The effort ties Mazda’s campus energy management setup to the storage unit to check for stable, high‑quality charging and discharging, and to look into how used batteries from hybrids, plug‑ins, fuel‑cell vehicles, and BEVs can be folded into industrial energy systems. The tests are described as a concrete move toward a scalable, circular battery ecosystem in line with Toyota’s Beyond Zero goals, aimed at cutting emissions while creating environmental and social value. The release notes that the system is meant to extend batteries’ useful lives and to help dampen the variability of renewable generation, potentially reducing demand for newly mined materials over time. Japanese media coverage adds that the tests aim to produce a replicable industrial model built on cross‑industry collaboration and resource circularity. That’s the idea, anyway.

Technically, the Sweep Energy Storage System is being shown off for its knack of handling batteries of varying ages and capacities, with real‑time monitoring and adaptive operation aimed at squeezing the best possible performance. That’s the goal. It reportedly doesn’t need external converters or inverters; it delivers energy in AC directly, which simplifies the overall setup and could trim installation costs. Industry coverage describes a modular, dynamic approach where individual battery flows can be rapidly switched to balance supply and demand, while the on‑board software keeps tabs on battery health and wear to decide when to engage or disengage the storage function. The field test is built to mesh with Mazda’s existing energy management framework and to feed into a larger renewable‑integration plan, including circular use of electrified‑vehicle batteries. The announcement says the collaboration also seeks to show a model that lowers barriers to scaling battery reuse for grid support.

Sweep can no longer be seen as a stand‑alone experiment. Honestly, this is a step beyond pilot tests. Earlier demonstrations laid the groundwork for large‑scale storage that uses reclaimed vehicle batteries and ties into Japan’s grid, including a dedicated installation at the Yokkaichi site that showcased a high‑capacity, grid‑connected solution. Toyota and JERA called that project a landmark for reusing electrified‑vehicle batteries to stabilize the grid, featuring a “sweep” function that enables full value extraction from diverse batteries and allows direct AC output by reusing onboard inverters and bypassing a separate power conditioner. Demonstration work at Yokkaichi, launched in 2022 and progressing through 2023, was intended to prove scalability and to reduce reliance on newly mined materials while cutting storage costs and supporting broader adoption of circular mobility‑energy solutions. Industry observers emphasise that this early large‑scale deployment laid the groundwork for the Hiroshima tests and for broader efforts to stabilise renewable energy through reused batteries.

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Source: Noah Wire Services