Since 2015
Custom battery pack projects
5,000 m²
Own factory
6 engineers
15+ years’ professional experience
60
Production-line employees
25+ countries
Traded with customers in
Choose the Right Platform for Your Custom Battery Pack
We deliberately focus on cylindrical lithium-ion cells. That focus lets our team go deep on the formats most OEM equipment actually uses and build custom battery solutions around them, instead of spreading across every battery category.
Custom 18650 Battery Packs
The 18650 cell (18 mm × 65 mm) suits compact devices where space is tight and a flexible series-parallel layout helps the pack fit the housing. We configure voltage, capacity, size, BMS, connectors and pack format around your device.
Custom 21700 Battery Packs
The larger 21700 cell (21 mm × 70 mm) is used for applications that need more energy, power or runtime. We design these packs around cell performance, space limits, current demand and heat dissipation.
Industrial Battery Packs
For industrial equipment, we prioritise reliability, mechanical integration, structural fit, safety requirements and continuity of supply – still built on our 18650 and 21700 engineering base.
What We Customize in Your Lithium-Ion Battery Pack
Voltage & Capacity
Nominal voltage and capacity sized to your device’s operating range and runtime target.
Series-Parallel Configuration
The cell arrangement (S/P) that delivers the voltage, capacity and current you need within the available space.
Pack Size & Shape
Cell layout and outer dimensions planned around your housing, mounting points and weight limits.
BMS & Protection
A protection scheme matched to your current profile and charging setup. BMS integration
Connectors & Wiring Harness
Connector type, wire gauge, lead length and pin-out defined to plug straight into your product.
Pack Format & Enclosure
The packaging form – from a wrapped cell pack to a pack in a protective housing – chosen for your mounting and environment.
Our Custom Battery Pack Design Process: From Requirements to Volume Supply
One engineering team follows your project from the first specification to series production, so decisions made during design carry through to the packs you receive.
01 Requirement Analysis
We review your application, electrical targets, space limits and volumes.
You receive: feasibility notes and a list of open questions.
02 Cell Selection
18650 or 21700, and the cell model that balances capacity, current capability and temperature range for your duty cycle.
You receive: cell options with datasheets and the trade-offs stated plainly.
03 Pack & BMS Design
Series-parallel layout, interconnects, structure, harness and BMS protection designed together and matched to your load, charger and interface.
You receive: pack configuration, layout drawing, BMS specification and a draft bill of materials for approval.
04 Sample Development
Prototype packs are built for fit checks and functional evaluation.
You receive: samples to test for fit and function in your own device.
05 Testing & Validation
Samples are verified against the agreed specification; required market and transport testing is planned in.
You receive: our test results, plus design changes where your field feedback requires them.
06 Volume Production
The approved design moves to series production with our assembly partners in Shenzhen, built to the same locked specification on every repeat order.
You receive: inspection records and shipping documents with each delivery.
Engineering, Manufacturing & Quality Under One Roof
Since 2015, Larnek Power has supported custom battery pack projects with its own factory covering 5,000 square meters, six engineers with more than 15 years of professional experience, and 60 production-line employees. We have traded with customers in over 25 countries, supporting battery pack development, prototyping and volume supply.
Because design and production sit with the same company, the engineers who specify your pack stay involved when it moves to the production line.
See why OEM teams work with Larnek Power as their custom battery pack manufacturer, or read more about our company and our capabilities.
Quality & Compliance, Planned from Day One
Cell quality – cells selected and sourced for the project’s performance and consistency needs.
Protection circuits – BMS and protection design reviewed against your current and charging profile.
Testing & validation – samples checked against the agreed specification before volume production.
Shipping documents – transport documentation for lithium battery shipments considered at quotation stage.
Target-market requirements – we discuss which standards your pack must meet (for example UN 38.3 transport testing or IEC 62133 safety testing) and confirm per project which tests and documents apply and how they will be provided.
Custom Battery Pack FAQs for Engineering & Procurement Teams
Your Battery Pack, Built Safe, Compliant and On Time
Backed by a strong Shenzhen supply chain, a dedicated engineering team and hands-on export experience, Larnek Power helps OEM teams move custom battery packs into production with consistent quality, competitive cost and the paperwork export requires.
Tell Us About Your Battery Project
Larnek Power supports OEM and industrial customers with custom 18650 and 21700 lithium-ion battery packs, from initial requirements and prototyping through volume production.
Tell us about your application, target voltage and capacity, size limits, current requirements, estimated quantity, and any drawings or existing battery details. Our engineering team will review your requirements and help define the next steps for your project.