Former Northvolt co-founder and CEO Peter Carlsson is returning to the energy sector with a new Stockholm-based startup, Sonder Labs, which is developing technology aimed at modernizing electrical grids.
Sonder Labs is still operating largely in stealth mode, but the company is gradually preparing for a public launch. Carlsson recently mentioned the startup publicly for the first time, revealing that its work will focus on sodium-based battery energy storage.
The company describes its ambition as building energy infrastructure that is “high-performing, sovereign and cost-efficient.”
A new venture in familiar territory
Sonder Labs is Carlsson’s second startup since the collapse of Northvolt. He is also a co-founder of Aris Machina, an agentic manufacturing company launched together with former Northvolt AI chief Siddharth Khullar.
While Aris Machina focuses on manufacturing, Sonder Labs takes Carlsson back into the energy-storage sector that made him one of Sweden’s best-known startup executives.
Sonder Labs is headquartered in Stockholm, like Aris Machina. The company is led by Andreas Haas, who serves as co-founder and CEO. Haas previously headed Northvolt’s sodium-ion division, giving the new company direct experience in one of the emerging alternatives to conventional lithium-ion batteries.
Carlsson and Haas have also recruited several former Northvolt executives and employees to join Sonder Labs.
€4.5M raised before public launch
Despite remaining in stealth, Sonder Labs has already secured significant early-stage financing.
The company raised approximately €4.5 million in its first funding round on June 1, at a reported pre-money valuation of around €10 million. The financing has not yet been formally announced by the company.
According to PitchBook, investors include Germany-based Ananda Impact Ventures and Vireo Ventures, as well as US-based Streetlife Ventures.
The company’s legal entity, Sonder Labs AB, and Carlsson’s involvement were first identified publicly in March.
Why sodium-ion batteries matter
Sonder’s focus on sodium-based energy storage comes at a time when grid-scale storage is becoming increasingly important for Europe’s energy transition.
Sodium-ion batteries are attracting attention as an alternative to lithium-ion technology because sodium is significantly more abundant and can potentially reduce dependence on critical raw materials and complex global supply chains.
For a company positioning itself around sovereign and cost-efficient energy infrastructure, that makes sodium-based storage a particularly relevant technology.
Sonder Labs has not yet disclosed detailed information about its technology, products or commercial plans. However, the combination of experienced former Northvolt executives, early funding and a focus on grid infrastructure suggests that the company is preparing for a significant entry into Sweden’s growing climate-tech ecosystem.
For Carlsson, Sonder Labs marks another attempt to build in the energy sector — this time with the experience of Northvolt’s rise and collapse behind him.
Startup: Sonder Labs
Headquarters: Stockholm, Sweden
Sector: Energy Infrastructure / Battery Storage
Technology: Sodium-ion energy storage
Funding: €4.5 million
CEO & Co-founder: Andreas Haas
Co-founder: Peter Carlsson
