Taking over Sony’s battery business (2017)

The cost of a second pillar outside the comfort zone

In September 2017 Murata took over Sony’s lithium-ion battery business, its most decisive attempt to build a second pillar beyond ceramic capacitors. It was also a step well outside the integrated-ceramics model on which Murata had always won — a business that shared little of the material science, the vertical integration or the customer base of the components that made the company. The logic was one of portfolio: batteries promised scale and a foothold in energy storage as smartphones, wearables and vehicles electrified. But the distance from Murata’s core showed up as time. Monetisation dragged, and restructuring charges kept recurring rather than fading.

By the year to March 2025 the strain was explicit — Murata booked a full year of battery restructuring charges and impaired already-ordered equipment for a cylindrical dry-cell line, and in 2026 it moved to hand its micro-primary-battery business to Maxell. The battery takeover belongs to the same pattern as the MEMS-sensor and filter acquisitions of the 2010s: bought to diversify away from the MLCC cycle, they instead needed years and repeated write-downs before they could pay. The very instinct that made Murata great — competing only where it holds an unmatched technical edge — is what makes ground outside that edge so costly to hold, and the battery business became the clearest measure of that cost.