XL Batteries
xlbatteries.com
Actively hiring
Chemical Manufacturing
Energy Storage
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Overview
News
Technologies
Salaries
Products
People
Growth
Offices
Financials
Funding and backers
Total raised
$36.1M
6 rounds on record
Latest round
$13M
Venture round · Jun 2026 · 3 mo ago
Team
51-200
employees, estimated range
Hiring now
3
open roles
Grants
$1.2M
2 grants · CORDIS
The money's age
Fresh money
3 months since the last round · hiring slowed
Momentum
35/100
in the news, fresh money
Last sign of life
this month
a posting or a news item
The story so fareach stage dated by its source: the company's releases, the press, registers, filings
Aug 6, 2025
Raised a round Venture round $7.5M · SEC Form D
Apr 22, 2024
Raised a round Venture round $7.7M · SEC Form D
Aug 24, 2022
Raised a round Venture round $8M · SEC Form D
2019
Founded
Funding rounds
| Round | Date | Amount | Investors | Source |
|---|---|---|---|---|
| Venture round | Jun 2026 | $13M | — | SEC Form D |
| Venture round | Aug 2025 | $7.5M | — | SEC Form D |
| Venture round | Apr 2024 | $7.7M | — | SEC Form D |
| Grant | Aug 2023 | $997k | — | CORDIS |
| Venture round | Aug 2022 | $8M | — | SEC Form D |
| Grant | Jun 2020 | $224k | — | CORDIS |
Registers and programsofficial lists and records that name the company
| Legal entity | XL Batteries, Inc. | SEC Form D |
Founders and leadersfrom filings, registers and the company's site
Thomas SistoExecutive Officer, DirectorSEC Form D
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News
XL Batteries Enters into a Memorandum of Understanding with ENEOS Holdings, Inc. to Advance Long-Duration Energy Storage
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XL Batteries Recognized as 2026 BloombergNEF Pioneer and "Most Inspiring Startup" by Data Center World
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Report
XL Batteries: $7.5 Million Raised For Long-Duration Energy Storage Solutions
XL Batteries is an innovative energy storage company that is focused on creating a new, more affordable, and safer way to store energy for long periods. Recently, the company announced a significant investment of $7.5 million from Merrin Investors, an org
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Report
XL Batteries Raises $7.5 Million From Merrin Investors to Accelerate Market Leadership in Organic, Non-Flammable, Long-Duration Flow Batteries
XL Batteries, an energy storage company that is building the lowest-cost, safest and most efficient form of long-duration energy storage (LDES), today announ...
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Prometheus Hyperscale and XL Batteries Partner to Deploy Long-Duration Energy Storage Systems at U.S. Data Centers
MARLBOROUGH, Mass. & EVANSTON, Wyo., May 14, 2025--XL Batteries, an energy storage company commercializing a revolutionary safe, low-cost and reliable grid-scale battery, and Prometheus Hyperscale (Prometheus), a leading developer of sustainable hyperscal
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Exclusive: XL Batteries is using petrochemical infrastructure to store solar and wind power
The startup has commissioned a demonstration unit of its organic flow battery.
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Tech stack
Technologies named in job postings at XL Batteries over the last 12 months, by layer, with the share of postings for each.
Technologies in use
12
Postings analysed
3
Stack modernity
71/100
Languages
C++
Python
Structured Text
C
Frameworks & libraries
ZeroMQ
Cloud & platforms
GitLab
GitLab CI
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Full XL Batteries tech stack
12 technologies · by team · pay by technology · changes · similar stacks
People
Thomas Sisto
Executive Officer, Director
Saif Qazi
Director
Jeffrey Schwarz
Director
Colin Nuckolls
Director
Jeffrey Smith
Director
Names and roles come from public filings, company registers and the company's own site. Is this you? Correct or remove · How we handle this data
Growth
Hiring Momentum
28/100
Slowing
Open positions
3
0 opened / 0 closed in 30 days
ATS activity
Every ~5 hours
Today
Hiring Dynamics
0%
Hiring Focus
The percentage next to each role is its share of the company's job openings over the last 90 days; the arrow shows the shift versus the previous period.
Finance
50% ▼
Early Careers
50% ▼
Offices
Where the company hires and what each office is for
Cities
2
Hiring now
2
Countries
1
Busiest office
Marlborough
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Headquarters
Builds here
Office with open vacancies
Tap a pin for the office
Marlborough
United States
HQ
Let's Work Together
2 open roles 2 posted in 90 days 50-200 est. staff
hires for Finance, Early Careers
Marlborough, MA 01752 USA
Boston
United States
Sales office
1 open roles 10-50 est. staff
hires for Finance
Financials
Total raised
$37.4M
Latest round
Venture - Series Unknown
Funding rounds
6