FSM

What FSM does

FSM AG is a privately held German electronics manufacturer founded in 1989 and headquartered in Kirchzarten near Freiburg, Germany. The company designs and produces intelligent electronic subsystems that are typically integrated as components inside customer end products across four business areas: Battery Management Systems (BMS) for lithium-ion battery packs, measurement technology, transformer switching relays (Trafosanfteinschalter / inrush current limiters), and E²MS — a full-service Electronics Development & Manufacturing offering spanning electronics and software design, prototyping, SMD/THT assembly, conformal coating, CNC machining, and lifecycle support. Its flagship BMS offering combines a standardized catalog line (BMSmart S/M/L for 2–10 cell series applications, with published unit pricing) with custom-engineered BMS solutions, complemented by a proprietary bidirectional USB-C universal charger (up to 240W, 48V).

FSM serves enterprise B2B customers in safety- and reliability-sensitive industries including medical devices (Boehringer Ingelheim, Fresenius Kabi, Weinmann Emergency), building automation (BELIMO), industrial measurement (JUMO), safety systems (HEKATRON), battery technology (VARTA), marine electric propulsion (Torqeedo), and automotive diagnostics (Hella Gutmann). The company monetizes through two complementary revenue streams: (i) hardware sales of BMS, measurement, and transformer switching products, and (ii) professional services across BMS development and E²MS contract manufacturing, with project lifecycles spanning consulting, design, prototyping, series production, and long-term after-sales support.

FSM operates a single manufacturing and engineering site in Kirchzarten with 125 employees, reached approximately EUR 29.5M in revenue in 2025, and is led by an Executive Board of Konrad Molz and Benjamin Schlegel under the Chairmanship of Eugen Molz. The company differentiates through functional safety expertise (IEC 61508, ISO 13849, ISO 26262), regulatory compliance support (UN 38.3, IEC 62133, UL 62133, EU Battery Regulation including digital Battery Passport), proprietary inline ICT/FCT test systems with a custom cell simulator, 2D QR-code traceability on every PCB, and a Germany-based vertically integrated production footprint.

Name

FSM

Legal name

FSM AG

Website

https://fsm.ag

Company type

Private

Founded year

1989

Operating status

Operating

Headcount range

101–250 employees

Short description

FSM AG is a privately held German electronics manufacturer founded in 1989 in Kirchzarten that designs and produces Battery Management Systems, measurement technology, transformer switching relays, and contract electronics manufacturing services (E²MS) for enterprise customers in medical, industrial, and e-mobility end markets.

Ownership category

akta.pro rank

Product category

Industrial Electronics Manufacturing

NAICS

Relay and Industrial Control Manufacturing (335314), Instruments and Related Products Manufacturing for Measuring, Displaying, and Controlling Industrial Process Variables (334513), Electrical Equipment Manufacturing (3353)

SIC

Electronic & Other Electrical Equipment (No Computer Equip) (3600), Industrial Instruments For Measurement, Display, And Control (3823), Switchgear & Switchboard Apparatus (3613)

akta.pro primary industry

Battery Management Systems (BMS) & Battery Electronics (IMAGAHAC)

akta.pro secondary industry

Battery Management System (BMS) & HV Control Electronics Manufacturing (IMACACAH)

Keywords

• Battery Management Systems
• Measurement Technology
• Electronics Manufacturing Services
• Transformer Switching Relays
• Custom Electronic Components

Headquarters

HQ city

Kirchzarten

HQ country

Germany

HQ region

Europe

Offices2 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Operations, Technology or R&D, Supply Chain, Marketing or Sales, Infrastructure

Revenue model

1. Battery Management Systems (BMS) Products: Sale of customized battery management systems including standard BMSmart product line (S, M, L variants) and custom BMS solutions. Products are typically integrated into customer end products as key electronic components.
2. BMS Development Services: Comprehensive development services covering electronics, software, layout, and mechanical development from initial product idea through prototyping to series production and product maintenance.
3. E²MS (Electronics Development & Manufacturing Services): Full-service electronics manufacturing including SMD/THT assembly, conformal coating, testing, and device assembly. Services span product engineering, supply chain management, industrial engineering, and packaging/logistics.
4. Measurement Technology Products: Measurement technology products and systems for various industrial applications.
5. Transformer Switching Relay Products: Inrush current limiters (TrafoSanfteinschalter) for transformer protection.

Pricing tiers

Go-to-market motion2 records

Distribution channels1 record

Marketing channels5 records

Core offering

FSM AG designs, develops, and manufactures intelligent electronic components and subsystems, with four core business areas: Battery Management Systems (BMS) for lithium-ion batteries, Measurement Technology (Messtechnik), Transformer Switching Relays (Trafosanfteinschalter), and E²MS (Electronics Development & Manufacturing Services). Most work is customer-specific and becomes an integrated part of the customer's end product.

Product overview

FSM AG is a German manufacturer of intelligent electronics offering four integrated business areas: Battery Management Systems (BMS), Measurement Technology, Transformer Switching Relays (Trafosanfteinschalter), and E²MS (development and manufacturing services for electronic components). The BMSmart product line provides standardized battery management systems (S, M, L variants) for quick deployment in 2-10 cell applications, complemented by a Bidirectional USB-C Universal Charger supporting up to 240W. Custom BMS development, prototyping, and series production services are available through E²MS. Manufacturing capabilities include SMD/THT assembly, press-fit technology, conformal coating, and mechanical processing. The company emphasizes functional safety compliance and regulatory certification support across all product areas.

Differentiator

Problem solved

Functional benefit

Brands

• BMSmart: Standard Battery Management System product line offering quick delivery and cost-effective solutions for small quantities, including BMSmart S, M, and L models.
• E²MS
• BMS (Batterie-Management-Systeme)
• Messtechnik
• Trafosanfteinschalter

Products and services

• BMSmart Standard Battery Management System Product Line Standardized battery management system product family (BMSmart S for 2-4 cells, BMSmart M for 4-6 cells, BMSmart L for 7-10 cells) featuring SMBus interface, gas gauging, balancing, over/under-voltage protection, short-circuit protection, temperature shutdown, and Second Level Protection. Targeted at manufacturers needing quickly available, cost-effective BMS for small production quantities.
• Bidirectional USB-C Universal Charger Integrated bidirectional charger supporting nearly any voltage up to 48V with up to 240W power delivery. Enables batteries to function as powerbanks. Designed for OEMs integrating USB-C charging into battery-powered products.
• Custom Battery Management System (BMS) Solutions Customer-specific Battery Management Systems for lithium-ion batteries with monitoring of voltage, current, and temperature. Includes 1st Level Protection (reversible) and 2nd Level Protection (irreversible), with BUS-system communication (I2C, SMBus, CAN, LIN, RS232). Built for manufacturers needing tailored BMS integrated into their end products.
• Measurement Technology (Messtechnik) Measurement technology products and systems for various industrial measurands and applications. Offered as one of FSM's four core business areas for industrial customers.
• Transformer Switching Relays (Trafosanfteinschalter) Soft-switching devices (inrush current limiters) for transformer protection. Offered as one of FSM's four core business areas for industrial customers requiring controlled transformer energization.
• E²MS (Electronics Development & Manufacturing Services) Full-service development and manufacturing services for electronic components covering product engineering, supply chain management, industrial engineering, testing technology, SMD/THT production, conformal coating, assembly, and packaging/logistics. Targets customers needing a single partner from consulting and development through series production.
• Battery Certification and Compliance Services Regulatory certification support for lithium-based battery packs covering UN 38.3 transport testing, IEC 62133 / UL 62133 safety certification with CB Report and UL certification options, UL 2054 certification for household and commercial devices, and EU Battery Regulation (EU 2023/1542) compliance including digital Battery Passport with lifecycle data, CO2 footprint, and recycling information.

Quantifiable outcome

• Up to 98% efficiency for USB-C charger technology
• +3 more outcomes

Named customers11 records

Segments4 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature6 records

Scale indicators5 records

Recent moves6 records

Expansion highlights5 records

Broad incumbents

• VARTA AG: German battery manufacturer spanning microbatteries, lithium-ion cells and energy storage solutions. Listed as an FSM customer (battery technology) but also a potential competitor in lithium-ion systems and integrated BMS at significantly larger scale.
• Analog Devices (BMS portfolio): Global semiconductor vendor offering battery management ICs and reference designs used inside industrial BMS boards. Comparable as the silicon platform that FSM competes against or integrates with, and as a broad incumbent in the underlying BMS technology stack.
• AKASOL (BorgWarner): German high-performance battery systems manufacturer for commercial vehicles, now part of BorgWarner. Overlaps with FSM's BMS and pack activities for e-mobility and industrial customers, but operates at much larger scale and is owned by a global Tier-1 supplier.
• Texas Instruments: Major semiconductor company whose battery monitor and protector IC family underpins much of the industrial BMS market. Competes with FSM at the silicon-reference-design layer and sets the cost benchmark that FSM's custom BMS designs must justify.

Emerging players

• IES Synergy: French designer and manufacturer of battery chargers and BMS for industrial, EV and stationary applications. Comparable niche specialist competing in the same BMS/charger space as FSM, with overlap on industrial and e-mobility customers.
• Ewert Energy Systems: US-based smaller BMS and battery monitoring product company serving EV, industrial and stationary storage OEMs. Comparable to FSM as a niche specialist competitor with overlapping customer use cases, though with a more standardized product go-to-market.

Direct peers

• Zollner Elektronik: Large German EMS provider offering electronics development and manufacturing services across medical, industrial and automotive customers. Directly comparable on the E²MS side of FSM's business and on customer type, though at materially larger scale and broader portfolio.
• BMZ Group: German manufacturer of lithium-ion battery systems and BMS solutions serving e-mobility, medical, industrial and power tool customers. Comparable in geography, vertical scope (cells-to-BMS-to-pack) and customer overlap with FSM, though larger in scale.
• Lithium Balance: Danish BMS specialist designing and manufacturing lithium-ion battery management systems for mobility, marine and industrial applications. Closest direct peer to FSM in product category, target customer profile (OEMs needing safety-certified BMS) and company scale.
• Elithion: US-based BMS developer offering custom and standard battery management systems for industrial, EV and stationary storage applications. Directly comparable as a small specialist BMS design house competing for similar OEM design wins.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights6 records

Customer concentration

• Xx.com/fsm_ag
• YouTubeyoutube.com/@fsmag2924
• Facebookfacebook.com/fsm.kirchzarten
• LinkedInlinkedin.com/company/fsm-ag
• Instagraminstagram.com/fsm_ag

Revenue estimate

Valuation estimate

Number of profiles

Profiles8 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about FSM