Nominal voltage
Custom cylindrical Li-ion battery pack engineering
Custom Li-ion Battery Packs
Custom rechargeable Li-ion battery packs built with 18650, 21700 and other approved cell formats. Voltage, capacity, discharge current, BMS, wiring, connectors and mechanical packaging are engineered around your OEM product.
Typical capacity
2Ah to 200Ah, project dependent
Cell formats
18650, 21700 & approved alternatives
Product details & applications
See how the solution is configured and applied.
The cell platform, bus structure, protection electronics and thermal sensing are selected as one approved assembly.
Voltage, current, runtime, connector and enclosure requirements are evaluated against the real device duty cycle.
Product overview
Engineered around the application.
Custom rechargeable Li-ion battery packs built with 18650, 21700 and other approved cell formats. Voltage, capacity, discharge current, BMS, wiring, connectors and mechanical packaging are engineered around your OEM product.
Key features
- Application-led selection of energy or power cells
- 1S to multi-series and series-parallel pack architecture
- 18650 and 21700 cylindrical Li-ion formats
- PCM or smart BMS integration with cell balancing
- Custom wire harnesses, connectors and communication
- Heat-shrink, molded plastic or metal enclosure options
- Thermal sensing, insulation and mechanical retention design
- Prototype, pilot and flexible OEM / ODM production
Common configurable ranges
Useful starting points for an RFQ.
These are selection ranges rather than fixed stock SKUs. Dimensions, capacity, load and interfaces must be evaluated together.
Common nominal voltage classes
3.6/3.7V7.2/7.4V10.8/11.1V14.4/14.8V18/18.5V21.6/22.2V24V class36V48V60V72V class
Cell and construction options
1865021700Energy cellPower cellHeat-shrink packMolded housingMetal enclosure
Control and interface options
Basic PCMBalancing BMSFuel gaugeNTC sensingUART / SMBusCAN / RS485Custom harness
Customization capabilities
Electrical, mechanical and interface options.
01
Nominal voltage
02
Usable capacity
03
Continuous current
04
Peak current
05
18650 / 21700 cell
06
Series / parallel layout
07
PCM / smart BMS
08
NTC thermistor
09
Wire gauge & length
10
Connector system
11
Communication protocol
12
Heat-shrink / housing
13
Mounting features
14
Label & packaging
Voltage architecture
Common Li-ion pack configurations.
These examples are engineering starting points, not fixed stock models. Cell voltage and final pack limits follow the approved cell and BMS specification.
3.6V / 3.7V nominal
Compact electronics, lighting and portable devices
7.2V / 7.4V nominal
Monitoring devices, instruments and smart hardware
10.8V / 11.1V nominal
Portable equipment, security and industrial electronics
14.4V / 14.8V nominal
Robotics, instruments and higher-power portable products
21.6V / 22.2V to 25.2V / 25.9V
Mobility, automation and application-specific equipment
36V to 72V class
Higher-voltage OEM systems, subject to engineering review
Cells & construction materials
Selected for electrical, thermal and mechanical requirements.
Cell chemistry is only one part of the pack. Interconnects, insulation, spacing, sensing and enclosure materials must work together as an approved assembly.
| Cell formats | Cylindrical 18650 and 21700 cells; other formats reviewed when the enclosure or load requires them. |
|---|---|
| Cathode systems | NMC, NCA or LCO-based Li-ion cells may be evaluated according to energy density, power, cycle life, availability and cost. |
| Cell enclosure | Steel-can cylindrical cells with insulating rings, sleeves and spacing selected for the approved construction. |
| Interconnection | Nickel strip, nickel-plated steel or engineered busbar construction selected according to current and pack architecture. |
| Insulation | Fish paper, PET barriers, cell holders, foam and heat-resistant insulating materials applied as required by the design. |
| Outer packaging | PVC/PET heat shrink, ABS/PC molded housing or metal enclosure, with brackets and sealing targets reviewed per project. |
Typical specifications
Detailed engineering discussion range.
Values below describe common feasibility discussions—not a guaranteed stock model. Final limits are confirmed in the approved specification, prototypes and project validation.
Electrical architecture and performance
| Battery type | Rechargeable cylindrical lithium-ion battery pack using an approved cell, protection system and mechanical construction |
|---|---|
| Cell formats | 18650 and 21700 are the primary cylindrical formats; another qualified format may be considered when the mechanical envelope or load requires it |
| Cell chemistry | NMC, NCA or LCO-based Li-ion options evaluated against energy density, power, cycle-life target, temperature, availability and cost |
| Nominal cell voltage | Typically 3.6V or 3.7V per cell; the selected cell datasheet and approved pack specification take precedence |
| Series / parallel architecture | 1S to multi-series packs with parallel groups sized for voltage, usable capacity, continuous current and pulse current |
| Common nominal pack voltages | 3.6/3.7V, 7.2/7.4V, 10.8/11.1V, 14.4/14.8V, 18/18.5V, 21.6/22.2V, 24V-class, 36V, 48V, 60V and 72V-class |
| Typical capacity discussion range | Approximately 2Ah to 200Ah; final capacity is constrained by voltage, cell platform, current, dimensions, weight and thermal design |
| Nominal energy | Calculated from nominal pack voltage × rated Ah capacity and stated in Wh on the approved specification |
| Charge method | Constant-current / constant-voltage charging, with pack charge limit, termination and pre-charge behavior matched to the cell count and BMS |
| Maximum charge voltage | Normally derived from the approved cell limit × series count; conventional Li-ion is often 4.20V per series cell |
| Charge current | Standard and maximum charge rates are selected from the cell specification, desired charge time, BMS, connector and thermal conditions |
| Continuous discharge current | Common project discussions may range from about 2A to 60A; the approved value depends on cells, parallel count, interconnects, BMS and cooling |
| Peak discharge current | Specified with pulse duration, repetition rate, minimum voltage, thermal recovery and BMS delay requirements |
| Cycle-life target | Commonly discussed from about 500 to 1,000+ cycles to an agreed retained-capacity criterion; no value is assumed without the final cell and duty cycle |
Protection, communication and interfaces
| Protection functions | Overcharge, over-discharge, over-current, short-circuit and temperature protection, with thresholds coordinated with the selected cell and host system |
|---|---|
| Cell balancing | Passive balancing or another approved strategy considered for multi-series packs where required by the application |
| BMS options | Basic PCM, balancing BMS or smart BMS with fuel gauging, event data and host communication |
| Communication options | Analogue state signals, UART, SMBus, CAN, RS485 or Bluetooth may be evaluated according to the system interface |
| Temperature sensing | One or more NTC thermistors or approved sensors positioned according to cell grouping, heat sources and charger requirements |
| Primary power connector | JST, Molex, XT-series, DC barrel, SM, Anderson-style or project-specified locking connector, selected for current and mating life |
| Signal connector | Separate or combined interface for NTC, identification, communication, enable and state signals where required |
| Wire harness | Conductor gauge, insulation, length, color, shielding, strain relief, exit direction, polarity and pinout defined in the approved drawing |
| Charger compatibility | Existing or proposed charger voltage, current, connector, communications and fault behavior reviewed before pack approval |
Mechanical, environmental and production
| Cell retention | Cell holders, structural adhesive, foam, spacers or brackets selected to manage movement, vibration, tolerance and assembly loads |
|---|---|
| Interconnection | Spot-welded nickel, nickel-plated steel or engineered busbars selected from current, resistance, weldability and fault requirements |
| Insulation system | Fish paper, PET barriers, terminal rings, sleeves, edge protection and heat-resistant materials placed according to the approved design |
| Outer construction | PVC/PET heat shrink, molded ABS/PC housing or metal enclosure with project-specific mounting and service strategy |
| Ingress and sealing target | Dust, splash or moisture targets are defined for the complete enclosure; no IP rating is assumed without validation |
| Operating temperature | Cell- and design-specific; discharge is often discussed around -20°C to 60°C while charging normally uses a narrower window |
| Mechanical validation | Fit, cable routing, connector retention, vibration, shock, drop or enclosure tests selected according to the host product risk assessment |
| Electrical validation | Capacity, runtime, voltage sag, charge behavior, protection response, current sharing and surface temperature evaluated to an agreed plan |
| Transport planning | UN 38.3 evidence and required shipping documentation confirmed for the final cell and pack configuration before transport |
| Compliance planning | IEC 62133, UL, CE, RoHS, REACH and market-specific requirements reviewed for the exact design; certification availability is not assumed |
| Traceability and change control | Approved cell, BOM, drawing revision, pack serial or lot data and controlled component substitutions defined for repeat production |
| Production support | Engineering review, samples, prototype iteration, pilot build, small batch, private label and OEM / ODM volume production |
| Commercial terms | MOQ, lead time, packaging, warranty and tooling are quoted after the technical configuration and validation scope are agreed |
Applications
Typical product uses.
IoT & monitoring equipment
Configuration is evaluated against the device load, available space, operating environment and production requirements.
GPS & asset trackers
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Security devices
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Robotics & automation
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Portable instruments
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Medical and wellness devices
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Lighting & emergency equipment
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Smart consumer hardware
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Mobility equipment
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Backup and communication devices
Configuration is evaluated against the device load, available space, operating environment and production requirements.
Engineering support
From requirements to production.
- 01Requirement Review
- 02Electrical Evaluation
- 03Solution Design
- 04Prototype Development
- 05Testing & Validation
- 06Pilot Production
- 07Mass Production
FAQ
Planning your custom project.
Is a custom lithium battery pack the same as a custom Li-ion battery pack?
For this product series, yes. “Custom lithium battery pack” is the broader buyer-facing term, while the main construction described here uses rechargeable cylindrical Li-ion cells such as 18650 or 21700. Small pouch LiPo batteries and 12V/24V LiFePO4 replacement batteries remain separate Meanwatt product series.
What information is needed to start?
Share the device input voltage, continuous and peak current, runtime target, maximum battery envelope, charging method, operating environment, connector, communication needs, target market and estimated quantity.
How are voltage and capacity configured?
Cells connected in series increase pack voltage, while parallel groups increase ampere-hour capacity and current capability. The final series-parallel architecture is checked against the load, charger, available space, thermal conditions and protection strategy.
Which cell material should we choose?
NMC, NCA and LCO-based Li-ion cells have different energy, power, cycle-life, availability and cost profiles. We select from approved cells only after the project priorities and operating conditions are understood.
Can the pack include a PCM or smart BMS?
Yes. Depending on complexity, the pack can use basic protection or a BMS with balancing, fuel gauging, data communication and temperature control. Functions are matched to the cell count, charger, load and host device.
Can Meanwatt develop prototypes?
Yes. Prototype and pilot stages can confirm electrical behavior, runtime, mechanical fit, connector pinout, thermal response and assembly details before volume production.
Are certifications automatically included?
No. Test reports and certification scope depend on the exact cell, pack design, target market and transport route. Required standards should be identified during project review and confirmed in writing.
Can you copy an existing battery pack?
An existing sample can help define dimensions, voltage, connector and interface requirements, but the new design must still be evaluated for cell availability, safety, intellectual-property considerations and system compatibility.
Faster engineering review
Send the details that define your application.
- Device and use environment
- Voltage, load and runtime
- Maximum dimensions
- Charging method
- Connector or interface
- Prototype and annual quantity
Start a project
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