Cylindrical 21700 High-Energy Cell
Amprius SA117
High-energy cylindrical 21700 cell delivering 5.9 Ah capacity with 288 Wh/kg energy density and 12 A maximum discharge rate.
Overview
The Amprius SA117 is a lithium-ion cylindrical 21700 cell designed for applications that demand high energy density and consistent capacity delivery. Released in 2025 and with the manufacturer based in the United States, this cylindrical 21700 cell delivers 5.9 Ah capacity and 20.77 Wh of energy at a nominal voltage of 3.52 V, with a maximum continuous discharge capability of 12 A, making it well suited to energy-focused applications requiring extended runtime.
Key Features
Discharge rate: 12 A continuous (2.0 C)
Energy density: 288 Wh/kg
Power density: 587 W/kg
Applications: aviation, e-mobility, energy storage
Technical Specifications from the Manufacturer
Parameter
Manufacturer
Amprius
Model
SA117
Type
Li-ion
Form factor
Cylindrical 21700
Country of origin
United States
Release year
2025
Nominal voltage
3.52
Energy capacity [Wh]
20.768
Capacity [Ah]
5.9
Gravimetric energy density [Wh/kg]
288
Gravimetric power density [W/kg]
587
Max continuous discharge [A]
12
Volume [cm³]
26.1191
Mass [g]
72
Positive electrode (cathode)
Negative electrode (anode)
Value
Applications & Use‑Cases
The Amprius SA117 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 Amprius SA117 across key indicators, including constant current behaviour, rate capability, temperature dependence, and available power under representative drive cycle conditions.
Constant Current Voltage
Access Amprius SA117 constant-current discharge curves in Voltt to size your pack against the voltage window your system actually needs. (Chart shown is illustrative, not SA117 data.)
Constant Current Temperature
Access Amprius SA117 thermal discharge data in Voltt to specify cooling and cell spacing before you commit to a pack layout. (Chart shown is illustrative, not SA117 data.)
Pulse Power Behaviour
Access Amprius SA117 pulse power maps in Voltt to set peak current limits and parallel count for your worst-case load. (Chart shown is illustrative, not SA117 data.)
Dynamic Profile Response
Access Amprius SA117 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 SA117 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 Amprius SA117 with similar Cylindrical 21700 cells offering comparable capacity and performance characteristics.
Model
Capacity
Max Discharge
Typical Use
Access Cell Data
Manufacturer Background
Amprius
Amprius Technologies is an American silicon-anode lithium-ion cell manufacturer
Amprius Technologies was founded in 2008 and is based in Fremont, California, where it develops and manufactures lithium-ion pouch cells built on silicon anodes rather than graphite. Its SiMaxx platform uses a silicon nanowire anode and sits at the high-energy end of the commercial market, while the SiCore platform is designed for production at larger volumes through manufacturing partners. The cells serve uncrewed aerial systems, electric aviation, defence and other weight-limited platforms where every gram of pack mass reduces endurance or payload. The company is scaling output at a large facility in Brighton, Colorado. Its position rests on bringing silicon-anode chemistry into qualified, shipping products.
Frequently Asked Questions
What is the capacity and voltage of the Amprius SA117?
The Amprius SA117 has a nominal capacity of 5.9 Ah and a nominal voltage of 3.52 V, providing 20.77 Wh of energy per cell.
What is the maximum continuous discharge capability of the Amprius SA117?
The Amprius SA117 supports continuous discharge rates up to 12 A, delivering a power density of 587 W/kg.
How much does the Amprius SA117 weigh and what is its volume?
The cell has a mass of 72 g and a volume of 26.12 cm³.
In which industries is the Amprius SA117 commonly used?
The Amprius SA117 is used across aviation, e-mobility and energy storage, applications that demand high energy density and consistent performance over extended cycles.
What is The Voltt and how does it accelerate cell evaluation?
The Voltt holds 500+ verified commercial cell datasheets alongside validated simulation models built from cells characterised in About:Energy's own lab. Engineers screen candidates against their real duty cycle before buying hardware, which cut cell evaluation time by seven months for McMurtry Automotive and reduces evaluation cycles by up to 70%.
What data can be extracted using The Voltt?
Constant-current discharge curves at multiple C-rates, DC internal resistance against state of charge and temperature, pulse power maps, thermal response, and full mission-profile simulation with user-defined pack configurations. Models are available as equivalent circuit, thermal, physics-based and degradation formats, exportable for use in MATLAB, Simulink and Python workflows.
