3500mAh High-Capacity Cell for Runtime-Focused Designs
The 18650-35E provides 3500mAh nominal capacity in the standard 18650 cylindrical format, giving battery designers more stored energy without increasing cell dimensions.
With an energy density of approximately 260Wh/kg, this cell is particularly suitable for products where battery space is limited but longer operating time is important. It offers a higher-capacity option for rechargeable devices that do not require the extreme current output of dedicated high-power cells.
High Energy Density with Practical Discharge Capability
The 18650-35E combines high capacity with enough discharge performance to support many portable and motor-driven devices.
Key electrical characteristics include:
- Nominal Capacity: 3500mAh @ 0.2C
- Minimum Capacity: 3400mAh
- Energy Density: Approx. 260Wh/kg
- AC Internal Resistance: ≤30mΩ
- Maximum Charge Current: 1C
- Maximum Discharge Current: 3C
- High-Rate Discharge: Suitable for 10A discharge-cycle conditions
This balance makes the 35E more suitable for energy and runtime-oriented applications than for equipment requiring sustained 20A–30A high-current output.
More Runtime from the Standard 18650 Format
For devices such as robot vacuums, portable speakers, and rechargeable personal-care products, increasing capacity at the cell level can extend operating time without requiring a larger battery enclosure.
The 3500mAh capacity of the 18650-35E can also help battery pack designers achieve a target energy requirement with fewer parallel cells compared with lower-capacity 18650 alternatives, depending on the voltage, current, and runtime requirements of the finished pack.
Cycle Performance for Frequently Recharged Equipment
Supplier testing indicates that the 18650-35E can achieve approximately 500 cycles under a 0.5C charge / 1C discharge condition while retaining at least 80% capacity.
This makes it suitable for products that undergo regular charging and discharging while still requiring consistent usable capacity over their service life.
Actual battery-pack cycle life will vary depending on depth of discharge, charge voltage, discharge current, operating temperature, thermal design, and BMS strategy.
Low-Temperature Discharge Capability
The 18650-35E also maintains useful energy output in colder environments. Supplier data indicates at least 70% discharge capacity at -20°C under a 0.2C discharge condition.
This provides additional operating flexibility for portable equipment that may experience seasonal temperature changes or occasional low-temperature use.
Typical Applications
The 18650-35E is particularly suited to rechargeable products that prioritize higher capacity and longer operating time, including:
- Robot vacuum cleaner battery packs
- Smart window-cleaning robot batteries
- High-capacity batteries for robotic vacuums
- RF beauty devices
- Facial cleansing brushes
- Portable water flossers
- Rechargeable personal-care devices
- High-capacity LED flashlights
- Portable Bluetooth speaker battery packs
- Other long-runtime portable electronic devices
For applications where very high continuous current is the primary requirement, a dedicated high-drain model such as the 18650-20P or 18650-25P would generally be a better fit.
Custom Battery Pack Integration
Lithogenix can integrate the 18650-35E into customized lithium-ion battery packs according to required voltage, capacity, runtime, current profile, dimensions, connector configuration, and protection requirements.
Pack development can include series-parallel configuration, BMS and protection design, wiring and connectors, enclosure integration, thermal considerations, and pack-level validation, helping translate the cell’s high-capacity characteristics into a battery solution suited to the target equipment.