Maxwell Technologies
Energy-storage and power-delivery technology company known especially for ultracapacitors and high-voltage capacitors.
Last updated August 22, 2026
AI crawler reads
2requests
1companies- Anthropic2
- Profile
- 2
- Controversies
- 0
- JSON · MD
- 0
- First read
- Nov 4, 2026
- Latest read
- Nov 4, 2026
From this site's server log
Overview
Maxwell Technologies is an American energy-technology company associated primarily with ultracapacitors, high-voltage capacitors, and related power-delivery systems. Its products and engineering capabilities have served automotive, heavy-transportation, renewable-energy, backup-power, wireless-communications, aerospace, industrial, and consumer-electronics applications. The company was founded in San Diego in 1965 as Maxwell Laboratories, Inc. by Raymond O'Rourke, Alan Kolb, Bruce Hayworth, and Terrence Gooding. It initially operated as a government contractor, undertaking advanced physics, pulsed-power, space-effects analysis, and research and development work for the U.S. military and other government agencies. During the early 1990s, Maxwell began shifting from predominantly government research toward commercial technologies and products. This transition ultimately made energy storage and power delivery the center of the business. The company adopted the Maxwell Technologies name in 1996. Its commercial portfolio included ultracapacitor cells and modules, high-voltage capacitor products, and other technologies intended to deliver rapid bursts of power, support regenerative braking, improve power quality, and complement batteries in demanding systems. By 2014, the company reported that all of its revenue came from commercial sources. Maxwell also retained links to aerospace and advanced electronics. In 2007, it won a contract valued at US$3 million from Astrium Satellites to provide computers for the European Space Agency's Gaia astronomy mission. Maxwell supplied seven SCS750 single-board computers for processing imagery and other data collected by the spacecraft. The company's product portfolio and corporate structure changed over time: its Maxwell Energy Products division, including the Maxwell High Voltage Capacitor line, was acquired by General Atomics in 2000 and later incorporated into General Atomics Electronic Systems; Maxwell sold its microelectronics product line to Data Device Corporation in 2016; and it acquired the core business and operating assets of Nesscap Energy in 2017 for US$23.175 million. The company expanded its manufacturing footprint with a facility in Peoria, Arizona, opened in 2013. That year it also signed a memorandum of understanding with SK Innovation to investigate next-generation electrical-energy storage combining Maxwell ultracapacitors with SK's lithium-ion batteries. The partnership reflected a broader industry interest in hybrid storage systems that combine the high power and rapid cycling of ultracapacitors with the higher energy density of lithium-ion batteries. Tesla announced an agreement to acquire Maxwell Technologies in February 2019, and the transaction closed on May 15, 2019, for approximately US$218 million. Maxwell subsequently operated within Tesla's portfolio for a limited period. In July 2021, Tesla sold the Maxwell name and ultracapacitor business to Ucap Power, a San Diego startup led by former Maxwell sales executive Gordon Schenk. The supplied reference material also reports an announcement in November 2025 that Maxwell was sold to Clarios for an undisclosed amount; the company's status and ownership after that reported transaction require verification against current corporate and regulatory sources.
History
Maxwell Technologies began in San Diego in 1965 as Maxwell Laboratories, Inc., a government-oriented research and engineering contractor founded by Raymond O'Rourke, Alan Kolb, Bruce Hayworth, and Terrence Gooding. Its early work covered advanced physics, pulsed power, space-effects analysis, and other research and development services for the U.S. military and government agencies. This origin gave the company expertise in high-energy electrical systems and specialized electronics, but the business later moved toward commercial products. The strategic transition began in the early 1990s, when Maxwell increasingly commercialized technologies developed through its research activities. In 1996, Maxwell Laboratories changed its corporate name to Maxwell Technologies. The company developed a market position around components capable of storing or delivering electrical energy rapidly, particularly ultracapacitors and high-voltage capacitors. These products were suited to applications requiring high power, rapid charge and discharge, long cycle life, or short-term energy buffering. Target markets included automotive systems, heavy transportation, renewable-energy installations, backup power, wireless communications, industrial equipment, aerospace, and electronics. Maxwell's portfolio was periodically reshaped through divestitures and acquisitions. General Atomics acquired Maxwell Energy Products, including the Maxwell High Voltage Capacitor product line, in March 2000. That business later became part of General Atomics Electronic Systems. Maxwell continued to pursue specialized electronics and aerospace opportunities, including a 2007 contract with Astrium Satellites to provide seven SCS750 single-board computers for the European Space Agency's Gaia astronomy mission. The computers were intended to process images and other data collected by the spacecraft's camera. The company expanded its manufacturing presence in 2013 by opening a facility in Peoria, Arizona. It also signed a memorandum of understanding with SK Innovation to study hybrid energy-storage systems combining Maxwell ultracapacitors with SK lithium-ion batteries. Such combinations were intended to pair the rapid power response and cycling capabilities of ultracapacitors with the energy-storage characteristics of lithium-ion cells. Maxwell's commercial transformation was substantially complete by 2014, when all of its revenue came from commercial sources according to the referenced account. In 2016, Maxwell completed the sale of its microelectronics product line to Data Device Corporation. In 2017, it acquired the core business, operating entities, and other assets of Nesscap Energy for US$23.175 million, reinforcing its presence in the ultracapacitor sector. These moves reflected an effort to focus the company on energy-storage and power-delivery technologies rather than maintaining a broad government-research and microelectronics portfolio. Tesla announced its intention to acquire Maxwell Technologies in February 2019. The acquisition closed on May 15, 2019, for approximately US$218 million. Maxwell's technologies were of interest to Tesla because ultracapacitors and related materials could complement battery systems and support electric-vehicle and energy-storage development. Tesla later divested the Maxwell branding and ultracapacitor business in July 2021, selling them to Ucap Power, a San Diego-based startup led by former Maxwell vice-president of sales Gordon Schenk. The supplied reference material further states that Maxwell was sold to Clarios in November 2025 for an undisclosed amount. Because that event is later than the principal historical milestones and its present corporate status is not otherwise documented in the supplied material, ownership and operating status should be checked against current authoritative sources.
- 2025
Reported sale to Clarios
[1]The supplied reference material reports a sale to Clarios in November 2025 for an undisclosed amount; current ownership requires verification.
- 2021
Ultracapacitor business transferred to Ucap Power
[1]Tesla sold the Maxwell brand and ultracapacitor business to Ucap Power.
- 2019
Tesla acquisition closes
[1]Tesla completed its acquisition of Maxwell Technologies on May 15, 2019.
- 2017
Nesscap Energy assets acquired
[1]Maxwell acquired Nesscap Energy's core business, operating entities, and related assets.
- 2016
Microelectronics business divestiture
[1]Maxwell sold its microelectronics product line to Data Device Corporation.
- 2013
Arizona manufacturing expansion and SK Innovation memorandum
[1]Maxwell opened a Peoria, Arizona facility and entered an agreement with SK Innovation to explore hybrid ultracapacitor and lithium-ion storage.
- 2007
Gaia mission computing contract
[1]Maxwell won a contract to supply SCS750 single-board computers for the European Space Agency's Gaia astronomy mission.
- 2000
Maxwell Energy Products is acquired by General Atomics
[1]General Atomics acquired Maxwell Energy Products, including the Maxwell High Voltage Capacitor line.
- 1996
Corporate name changes to Maxwell Technologies
[1]Maxwell Laboratories, Inc. adopted the Maxwell Technologies, Inc. name.
- 1990
Shift toward commercial technology
[1]During the early 1990s, the company began converting its research capabilities into commercial applications and products.
Products and positioning
High-power, fast-response energy-storage and power-delivery technology provider serving transportation, renewable-energy, industrial, aerospace, and electronics applications.
Energy storage
Ultracapacitors
Maxwell's best-known products were ultracapacitor cells and modules designed for rapid charge and discharge, high power delivery, and extensive cycling. They were positioned for automotive and heavy-transportation systems, regenerative-braking support, renewable-energy buffering, backup power, industrial equipment, and other applications where short-duration power and response speed were more important than maximum energy density.
Capacitors and power delivery
High Voltage Capacitors
The Maxwell High Voltage Capacitor line formed part of the company's energy-products portfolio. The division was sold to General Atomics in 2000 and subsequently became part of General Atomics Electronic Systems. The products served specialized high-voltage and power-delivery requirements rather than ordinary consumer electronics applications.
Aerospace computing
SCS750 Single-Board Computers
Maxwell supplied seven SCS750 single-board computers for the European Space Agency's Gaia astronomy mission through a 2007 contract with Astrium Satellites. The computers were intended to process images and other data collected by the spacecraft's camera, illustrating Maxwell's earlier and continuing involvement in ruggedized and specialized computing for aerospace applications.
Energy storage systems
Energy Storage Modules
Maxwell marketed assembled ultracapacitor modules and related power-delivery solutions for integration into transportation, renewable-energy, industrial, and backup-power systems. These modules were intended to simplify system integration by combining multiple storage elements with the electrical interfaces and packaging required by larger equipment.
Brand decisions
2021
Tesla divests Maxwell brand and ultracapacitor businessM&ABackground
Tesla decided to sell the Maxwell Technologies branding and ultracapacitor operation after acquiring the company in 2019.
Action taken
Tesla transferred the brand and ultracapacitor business to Ucap Power, a San Diego startup led by former Maxwell sales executive Gordon Schenk.
Aftermath
The Maxwell name and ultracapacitor business returned to an independent specialist operator outside Tesla.
2019
Tesla acquisitionM&ABackground
Tesla announced a plan to acquire Maxwell Technologies, whose ultracapacitor and related energy technologies were relevant to electric-vehicle and energy-storage development.
Action taken
Tesla completed the acquisition on May 15, 2019.
Aftermath
Maxwell became part of Tesla's portfolio until Tesla divested the brand and ultracapacitor business in 2021.
Acquisition consideration. US$218 million (May 15, 2019)
2017
Acquire Nesscap Energy assetsM&ABackground
Maxwell sought to strengthen its ultracapacitor business and expand its operating assets.
Action taken
Maxwell acquired Nesscap Energy's core business, operating entities, and related assets.
Aftermath
The acquisition expanded Maxwell's position in the ultracapacitor sector.
Purchase price. US$23.175 million (2017)
2016
Divest the microelectronics product lineStrategyBackground
Maxwell was narrowing its portfolio around energy storage and power delivery.
Action taken
The company sold its microelectronics product line to Data Device Corporation.
Aftermath
The divestiture reduced Maxwell's exposure to microelectronics and supported a more focused energy-technology strategy.
1990
Move from government contracting toward commercial productsStrategyBackground
Maxwell originated as a government research and engineering contractor but sought to commercialize its advanced physics, pulsed-power, and related technologies.
Action taken
Beginning in the early 1990s, the company redirected its business toward commercial energy-storage and power-delivery applications.
Aftermath
By 2014, the referenced account states that all of Maxwell's revenue came from commercial sources.
Recent events
Reported
Phase Four announces Maxwell Block 2 and Block 3 engines[3]
Phase Four announced the expansion of its Maxwell propulsion line with Maxwell Block 2, which was available for order with deliveries beginning in Q1 2022, and Maxwell Block 3, scheduled for delivery in the second half of 2022.
Reported
Maxwell launches MaxDiligence[4]
Maxwell released MaxDiligence, a new service offering due diligence and quality control services for its clients, including community lenders.
Reported
Tesla completes acquisition of Maxwell Technologies[5]
Tesla completed its acquisition of Maxwell Technologies through the second-step merger after accepting shares tendered in its exchange offer.
Sources6 sources
- 1Maxwell Technologiesen.wikipedia.org
- 2Maxwell Technologies official websitemaxwell.com
- 3Phase Four宣布Maxwell Block 2和Block 3发动机prnewswire.com
- 4Maxwell 推出 MaxDiligenceprnewswire.com
- 5特斯拉完成对麦克斯韦科技的收购spacemart.com
- 6Maxwell Introduces MaxDiligence, Due Diligence And QC Service For Lendersnationalmortgageprofessional.com
Cite this profile: Cite the canonical profile. /brand-wiki/maxwell-technologies · Editorial policy · How profiles are compiled