THOR 303040 3.7V 300mAh lithium polymer battery with PCM protection, red and black lead wires, and 2-pin connector

THOR 303040 3.7V 300mAh LiPo battery dimension drawing showing T×W×L = 3 × 30 × 42 mm (with PCM) and 2-pin connector polarity

Customizable LiPo battery connector and wire harness options, with PH 2.0 mm shown for reference

Lithium polymer (LiPo) battery connector polarity guide showing red positive and black negative wires with correct and incorrect connection examples

THOR lithium polymer (LiPo) battery discharge performance comparison with discharge curves and microscopic electrode material images

↓ Download Product Datasheet (PDF)Request a Quote

Description

The THOR-303040 is a 3mm-class, 300mAh pouch cell with a 30 × 40mm footprint. THOR-303442 keeps the same 3mm thickness and increases capacity to 350mAh by expanding to 34 × 42mm, while THOR-403035 reaches 350mAh in a shorter 30 × 35mm footprint by increasing thickness to 4mm. THOR-303040 is the selection when the 3mm thickness ceiling matters more than maximizing capacity.

The 3.0 × 30 × 40mm dimension is the nominal bare-cell envelope. The finished battery can be larger once the PCM, insulation, lead exit and connector are added, which is especially important in shallow enclosures. Verify protected-pack thickness, nearby PCB components, ribs and connector routing before freezing the mechanical design.

At 3.7V nominal, the 300mAh rating corresponds to 1.11Wh. Device runtime depends on load shape, regulator efficiency, cutoff voltage, wireless, display or sensor duty cycle, temperature and aging. No discharge-rate claim should be derived from the thin profile or 300mAh capacity without model-specific validation.

THOR-303040 Engineering & Fit Questions

How does THOR-303040 compare with THOR-303442?

THOR-303442↗ keeps the same 3mm thickness but expands the footprint from 30 × 40mm to 34 × 42mm and increases capacity from 300mAh to 350mAh.

Why choose THOR-303040 instead of a 4mm-thick alternative?

THOR-303040 protects a 3mm thickness ceiling. A model such as THOR-403035↗ can provide 350mAh in a shorter footprint, but it requires 4mm thickness.

Are 3 × 30 × 40mm the finished protected-pack dimensions?

No. They are the bare-cell dimensions. PCM, wires, connector, insulation, pouch expansion and production tolerances must be added to the enclosure study.

Stable 3.7 V nominal output for reliable power delivery
Long cycle life — typically several hundred cycles, cost-efficient
Built-in protection: overcharge, over-discharge, short-circuit
Custom size, capacity, connector & PCM/BMS
UN38.3 / MSDS ready; CE, KC, ROHS on request

Why Choose THOR Power

A vertically integrated lithium battery manufacturer (Dengzhou Xinju New Energy) with the scale and engineering depth to deliver custom LiPo cells reliably at volume.

3 factories, 800+ staff

Source-manufacturer scale — not a trading company.

200+ engineers

R&D led by a chief battery scientist for rapid custom design.

60,000 pouch cells / day

High-volume manufacturing with products exported across the US, Europe, Japan & Korea, SE Asia, Latin America and Africa.

End-to-end quality control

From raw material to finished cell.

Factory Photos

Automation Equipment

Testing Equipment

Warehouse & Certifications

Model	THOR-303040
Battery Type	Lithium Polymer (LiPo) pouch cell
Capacity	300 mAh
Certifications	UN38.3 / MSDS (IEC 62133-2, CE, KC on request)
MOQ	From 10 pcs for samples; production quoted per project
Customization	Size, capacity, connector, wire length, PCM/BMS, NTC, label

THOR-303040 3.7V 300mAh LiPo Battery – 3×30×40mm

The THOR-303040 is a 300mAh 3.7V lithium polymer battery with a 3.0 × 30 × 40mm bare-cell envelope and approximately 1.11Wh nominal energy. Its broad, very thin geometry may suit slim smart badges, rechargeable ID cards, sensor patches or tracking labels where battery depth is tightly constrained. Final suitability should be confirmed against the protected-pack dimensions, load profile, connector and wire-routing requirements.

Wholesale Pricing (USD)

Order Quantity	Reference Unit Price
10 – 99 pcs	—
100 – 999 pcs	—
1,000 – 9,999 pcs	—
10,000+ pcs	Contact for best price

Reference pricing for this model is being finalised. Talk to a Battery Engineer for a same-day quote.

Prices are for standard configuration reference only. Final pricing may vary by cell size, capacity, connector, wire length, PCM/BMS, label, packaging, certification requirements, and order quantity. Shipping cost is not included. MOQ: from 10 pcs for samples; production quantities are quoted per project.

Get an Engineering Quote

Custom sizes, capacities, connectors & PCM/BMS available. MOQ-friendly. Samples in days.

Battery Specification — THOR-303040

Mechanical Characteristics

Model	THOR-303040
Cell Type	Lithium Polymer (LiPo) pouch cell
Configuration	1S1P (customizable)
Dimensions (T×W×L)	3 × 30 × 40 mm (bare cell)
Dimension Tolerance	Thickness ±0.2 mm; Width/Length ±0.5 mm
With PCM Board	Length approx. +2 mm vs bare cell
Weight	Approx. 8 g
PCM / BMS	Included (standard)
NTC Thermistor	Optional
Connector	PH2.0 / Molex 1.25 (custom available)
Wire Length	Customizable
UN38.3	Test Summary available
Safety Data Sheet	SDS / MSDS available
IEC 62133-2	Available for selected models
RoHS / REACH	Compliance documents available

Electrical Specifications

Nominal Voltage	3.7 V
Rated Capacity	300 mAh
Energy	1.11 Wh
Charge Voltage	4.20 ± 0.03 V
Standard Charge	60 mA (0.2C), CC/CV to 4.20 V
Charge Cut-off Current	0.02C
Max. Charge Current	300 mA (up to 1C), model-specific
Discharge Cut-off Voltage	3.0 V
Standard Discharge	60 mA (0.2C)
Max. Continuous Discharge	300 mA (1C), model-specific
Internal Resistance	≤ 130 mΩ (1 kHz, 50% SOC, 25℃)
Cycle Life	≥ 500 cycles, ≥ 80% capacity
Cycle Test Condition	0.5C charge / 0.5C discharge, 3.0-4.2 V, 25 ± 2℃
Charge Temperature	0℃ ~ 45℃
Discharge Temperature	-20℃ ~ 60℃
Storage Temperature	-10℃ ~ 45℃ (≤ 1 month)
Capacity Retention	≥ 90% after 28 days @ 25℃
Note	Higher discharge-rate designs available upon engineering review

Protection Circuit (when PCM equipped)

Overcharge Detection	4.28 ± 0.03 V per cell
Overcharge Release	4.08 ± 0.05 V
Over-discharge Detection	2.75 ± 0.05 V
Over-discharge Release	3.00 ± 0.05 V
Overcurrent Protection	Per PCM design (2A ~ 5A typical)
Short-circuit Protection	Yes, auto-recovery

Values shown are THOR Power standard specifications for this cell class. Final parameters are confirmed in the engineering datasheet for your configuration.

Typical Applications — THOR-303040

Slim Smart Badges & Rechargeable ID CardsPrimary technical-fit use for a broad 30 × 40mm footprint where a 3mm cell thickness is the controlling mechanical constraint.

Adhesive Wearable Sensor PatchesA candidate for thin sensing patches after bending, skin temperature, duty cycle and finished-pack clearance are evaluated.

Thin Asset Tags & Tracking LabelsSuitable for low-profile rechargeable tags with validated standby drain, radio pulses, enclosure stiffness and antenna spacing.