Pouch Cell
Amprius SA129
Pouch cell delivering 14.5 Ah capacity with 302 Wh/kg energy density and 72.5 A maximum discharge rate.
Overview
The Amprius SA129 is a lithium-ion pouch cell designed for applications that demand reliable performance across a broad range of load conditions. Released in 2025 and with the manufacturer based in the United States, this pouch cell delivers 14.5 Ah capacity and 51 Wh of energy at a nominal voltage of 3.52 V, with a maximum continuous discharge capability of 72.5 A, making it suitable for applications that balance runtime against peak power demand.
Key Features
Discharge rate: 72.5 A continuous (5.0 C)
Energy density: 302 Wh/kg
Power density: 1,510 W/kg
Applications: drones, aviation, e-mobility
Technical Specifications from the Manufacturer
Parameter
Manufacturer
Amprius
Model
SA129
Type
Li-ion
Form factor
Pouch
Country of origin
United States
Release year
2025
Nominal voltage
3.52
Energy capacity [Wh]
51.04
Capacity [Ah]
14.5
Gravimetric energy density [Wh/kg]
302
Gravimetric power density [W/kg]
1510
Max continuous discharge [A]
72.5
Volume [cm³]
75.8352
Mass [g]
169
Positive electrode (cathode)
Ni-based
Negative electrode (anode)
Value
Applications & Use‑Cases
The Amprius SA129 is well suited to the following applications due to its pouch form factor and balanced performance.
Drones: Demands high gravimetric power density for thrust and payload capacity, rapid current response for flight control, and stable voltage delivery across dynamic flight profiles.
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.
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 SA129 across key indicators, including constant current behaviour, rate capability, temperature dependence, and available power under representative drive cycle conditions.
Constant Current Voltage
Access Amprius SA129 constant-current discharge curves in Voltt to size your pack against the voltage window your system actually needs. (Chart shown is illustrative, not SA129 data.)
Constant Current Temperature
Access Amprius SA129 thermal discharge data in Voltt to specify cooling and cell spacing before you commit to a pack layout. (Chart shown is illustrative, not SA129 data.)
Pulse Power Behaviour
Access Amprius SA129 pulse power maps in Voltt to set peak current limits and parallel count for your worst-case load. (Chart shown is illustrative, not SA129 data.)
Dynamic Profile Response
Access Amprius SA129 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 SA129 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 SA129 with similar Pouch 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 SA129?
The Amprius SA129 has a nominal capacity of 14.5 Ah and a nominal voltage of 3.52 V, providing 51 Wh of energy per cell.
What is the maximum continuous discharge capability of the Amprius SA129?
The Amprius SA129 supports continuous discharge rates up to 72.5 A, delivering a power density of 1,510 W/kg.
How much does the Amprius SA129 weigh and what is its volume?
The cell has a mass of 169 g and a volume of 75.8 cm³.
In which industries is the Amprius SA129 commonly used?
The Amprius SA129 is used across drones, aviation and e-mobility, applications that demand reliable performance and balanced energy and power.
How does the Amprius SA129 compare with the Enpower Greentech XNP0150J?
Comparing the Amprius SA129 with the Enpower Greentech XNP0150J: capacity 14.5 Ah against 15 Ah; maximum continuous discharge 72.5 A against 45 A; energy density 302 Wh/kg against 349 Wh/kg; mass 169 g against 149 g. Both datasheets can be compared side by side in The Voltt.
What chemistry and format is the Amprius SA129?
The Amprius SA129 is a pouch cell. It has a nominal voltage of 3.52 V and a volume of 75.8 cm³. Its full datasheet is free to view in The Voltt.
