As artificial intelligence (AI) servers drive a revolution in power infrastructure, one critical component is quietly becoming indispensable: the back battery unit, or BBU. Increasingly, these BBUs are being equipped with Electric Double Layer Capacitor (EDLC), a shift that's already reshaping the industry.
Supercapacitors, a high-end product category among global passive component makers, are seeing surging demand amid the AI boom. Taiwanese conglomerate Yageo Group has been aggressively expanding its presence in this space, acquiring Japanese and American manufacturers to bring advanced capacitor product lines under its umbrella.
Leading suppliers worldwide — from Japan's Rubycon, Nichicon, and Chemicon, to America's Maxwell and Eaton, and South Korea's VINATech and Korchip — are all racing to develop next-generation supercapacitors. Kemet, a Yageo subsidiary, is also a major player with a robust portfolio of high-performance capacitors.
Among Taiwanese battery module makers, AES and Dynapack stand out. Dynapack President Chung-Hsing Chang says demand for high-end AI servers is accelerating, driving up power consumption and the share of systems equipped with BBUs. The integration of supercapacitors into BBUs is no longer just a concept; it's happening now, he noted.
Scaling up for AI's power demands
In anticipation of this growth, Dynapack is ramping up production. The company currently makes lithium-ion battery modules for consumer electronics in China and Thailand, and manufactures BBUs in Thailand and Taiwan. Chang says both facilities will expand, doubling BBU output by 2026 compared with 2025.
Though BBUs have yet to become standard in all AI servers, their adoption is climbing fast. Chang notes that at least three major cloud service providers (CSPs) have already implemented BBUs, with both penetration rates and power capacities increasing. Shipments in 2025 will feature 3kW BBUs, while 2026 products will reach 8kW — with some models ranging from 8 to 12kW.
Redesigning the server for the AI era
The surge in AI computing power has led to a corresponding spike in energy consumption — sparking what Chang calls a "power revolution." Every aspect of server design is being rethought: chassis, power systems, cabling, cooling, and BBUs. To handle potential outages, BBUs need larger capacities, which means physically larger units as well.
As these power modules grow in size, next-generation systems are shifting from traditional 400V setups to high-voltage direct current (HVDC) architectures of 800V. Instead of squeezing everything into a single rack, new "sidecar" designs are emerging, integrating the power supply and BBU into a separate cabinet.
Chang says the company is already developing BBUs optimized for 400V and 800V HVDC systems, with higher energy and power densities, and incorporating next-generation high-capacity cells and supercapacitor options. These designs are currently being qualified by customers and are expected to enter mass production in 2027.
Riding the AI wave
The rollout of systems based on Nvidia's Vera Rubin Ultra architecture is still underway, but BBU adoption is already soaring — fueling strong performance for suppliers such as Dynapack and AES.
AES reported NT$4.13 billion (approx. US$133.2 million)in consolidated revenue for the third quarter, up 74.6% year-over-year, with a 34.9% gross margin and NT$798 million in net profit, up 49.1%. BBUs now account for more than 70% of its quarterly sales.
Dynapack, meanwhile, still derives most of its revenue from notebook and consumer-electronics battery modules, a segment hit by sluggish PC demand. Fortunately, growth in BBUs and other non-consumer applications has helped offset the slowdown. In the first three quarters of 2025, consumer electronics made up 60–70% of Dynapack's revenue, with 30–40% coming from non-consumer products — mostly BBUs.
Chang says fierce competition in the notebook market has dragged down shipments and sales, and the company had expected a 20% decline in 2025 revenue. However, stronger-than-expected demand for non-consumer products has narrowed that forecasted drop to under 10%.
Looking ahead, Chang expects non-consumer electronics to rise to 40–50% of revenue by 2026 — a shift that will also boost profitability, given the higher margins in that segment. For the third quarter, Dynapack posted NT$3.62 billion in revenue, with a 16.1% gross margin and a 9.4% net margin, both higher than the previous quarter.
Article translated by Elaine Chen and edited by Jack Wu
