Cylindrical 21700 High-Energy Cell
SES 58E
High-energy cylindrical 21700 cell delivering 5.8 Ah capacity with 298 Wh/kg energy density and 5.8 A maximum discharge rate.
Overview
The SES 2170-58E is a lithium-ion cylindrical 21700 cell designed for applications that demand high energy density and consistent capacity delivery. With the manufacturer based in the United States, this cylindrical 21700 cell delivers 5.8 Ah capacity and 20.9 Wh of energy at a nominal voltage of 3.6 V, with a maximum continuous discharge capability of 5.8 A, making it well suited to energy-focused applications requiring extended runtime. Among the 21700 cylindrical cells in the About:Energy battery library, the SES 58E ranks 11th of 97 for gravimetric energy density. Its 298 Wh/kg compares with a 21700 cylindrical median of 257 Wh/kg.
Key Features
Discharge rate: 5.8 A continuous (1.0 C)
Energy density: 298 Wh/kg
Power density: 298 W/kg
Cathode: Ni-based
Applications: aviation, e-mobility, energy storage
Technical Specifications from the Manufacturer
Parameter
Manufacturer
SES
Model
2170-58E
Type
Li-ion
Form factor
Cylindrical 21700
Country of origin
United States
Release year
2026
Nominal voltage
3.6
Energy capacity [Wh]
20.88
Capacity [Ah]
5.8
Gravimetric energy density [Wh/kg]
298
Gravimetric power density [W/kg]
298
Max continuous discharge [A]
5.8
Volume [cm³]
24.8858
Mass [g]
70
Positive electrode (cathode)
Ni-based
Negative electrode (anode)
Graphite/Si additive
Value
Applications & Use‑Cases
The SES 58E is well suited to the following applications due to its cylindrical 21700 form factor and high energy density performance.
Aviation: Requires high specific energy for extended flight duration, high power-to-weight ratio for climb performance, and reliable operation across wide temperature ranges at altitude.
E-Mobility: Requires balanced energy and power density for range and acceleration, high cycle life for daily use, and robust calendar life to ensure long-term reliability.
Energy Storage: Requires stable cycle life across deep discharge profiles, reliable calendar life under float conditions, and consistent capacity retention over extended deployment periods.
General Applications: Suitable for applications requiring reliable lithium-ion performance with proven cycle life, consistent capacity delivery, and operational safety across diverse use cases.
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Performance & Model Data
Below are modelled performance metrics for the SES 58E across key indicators, including constant current behaviour, rate capability, temperature dependence, and available power under representative drive cycle conditions.
Constant Current Voltage
Access SES 58E constant-current discharge curves in Voltt to size your pack against the voltage window your system actually needs. (Chart shown is illustrative, not 58E data.)
Constant Current Temperature
Access SES 58E thermal discharge data in Voltt to specify cooling and cell spacing before you commit to a pack layout. (Chart shown is illustrative, not 58E data.)
Pulse Power Behaviour
Access SES 58E pulse power maps in Voltt to set peak current limits and parallel count for your worst-case load. (Chart shown is illustrative, not 58E data.)
Dynamic Profile Response
Access SES 58E mission profile simulations in Voltt to prove the pack holds up over a real duty cycle before you build it. (Chart shown is illustrative, not 58E data.)
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Case Studies
See how we helped McMurtry reduce cell evaluation time by 70% through data driven testing and modelling.
Motorsports
McMurtry Automotive: Faster cell evaluation
McMurtry Automotive used The Voltt and validated cell models to evaluate the transition from the Molicel P45B to P50B during early pack concept development.
Side by side modelling enabled rapid comparison of electrical and thermal behaviour, avoiding lengthy physical test campaigns. This approach reduced cell evaluation time by seven months, allowing the team to lock in cell selection and pack assumptions earlier while lowering technical risk and accelerating vehicle development.
Comparison with Related Cells
Compare the SES 58E with similar Cylindrical 21700 cells offering comparable capacity and performance characteristics.
Model
Capacity
Max Discharge
Typical Use
Access Cell Data
Manufacturer Background
SES AI
SES AI is an American developer of lithium-metal and lithium-ion cells
SES AI was founded in 2012 as SolidEnergy Systems and is headquartered in Boston, Massachusetts, with operations in Singapore, Shanghai and South Korea. The company develops both lithium-metal and lithium-ion pouch cells, pairing them with electrolyte formulations identified through its own AI-driven materials discovery platform. Its cells serve uncrewed aerial systems, electric aviation and automotive development programmes where energy density is the binding constraint, and the company also licenses its materials discovery software to other manufacturers. SES AI is publicly listed and works with automotive partners on joint development. It sits among the small group of developers moving lithium metal from laboratory demonstration toward qualified production.
Frequently Asked Questions
What is the capacity and voltage of the SES 58E?
The SES 58E has a nominal capacity of 5.8 Ah and a nominal voltage of 3.6 V, providing 20.9 Wh of energy per cell.
What is the maximum continuous discharge capability of the SES 58E?
The SES 58E supports continuous discharge rates up to 5.8 A, delivering a power density of 298 W/kg.
How much does the SES 58E weigh and what is its volume?
The cell has a mass of 70 g and a volume of 24.9 cm³.
In which industries is the SES 58E commonly used?
The SES 58E is used across aviation, e-mobility and energy storage, applications that demand high energy density and consistent performance over extended cycles.
How does the SES 58E compare with the Tenpower 58HE?
Comparing the SES 58E with the Tenpower 58HE: capacity 5.8 Ah against 5.65 Ah; maximum continuous discharge 5.8 A against 12.5 A; energy density 298 Wh/kg against 283 Wh/kg; mass 70 g against 72 g. Both datasheets can be compared side by side in The Voltt.
What chemistry and format is the SES 58E?
The SES 58E is a cylindrical 21700 cell with a Ni-based cathode and a Graphite/Si additive anode. It has a nominal voltage of 3.6 V and a volume of 24.9 cm³. Its full datasheet is free to view in The Voltt.
