Cylindrical 21700 High-Power Cell
BAK 45D
High-power cylindrical 21700 cell delivering 4.4 Ah capacity with 230 Wh/kg energy density and 60 A maximum discharge rate.
Overview
The BAK INR2170-45D is a high-power Li-ion cylindrical 21700 cell designed for applications that demand sustained high current and high energy density. Manufactured in china, this cylindrical 21700 cell delivers 4.4 Ah capacity and 15.84 Wh of energy at a nominal voltage of 3.6 V, with a maximum continuous discharge capability of 60 A, making it well suited to high-power systems operating under aggressive load profiles.
Key Features
Extremely high discharge rate: 60 A continuous (13.6 C)
Energy density: 230 Wh/kg
Power density: 3130 W/kg
Applications: aviation, motorsports, e-mobility
Technical Specifications from the Manufacturer
Parameter
Manufacturer
BAK
Model
INR2170-45D
Type
Li-ion
Form factor
Cylindrical 21700
Country of origin
China
Release year
2023
Nominal voltage
3.6
Energy capacity [Wh]
15.84
Capacity [Ah]
4.4
Gravimetric energy density [Wh/kg]
230
Gravimetric power density [W/kg]
3130
Max continuous discharge [A]
60
Volume [cm³]
25.57
Mass [g]
69
Positive electrode (cathode)
Ni-based
Negative electrode (anode)
Graphite/Si additive
Value
Applications & Use‑Cases
The BAK INR2170-45D is well suited to the following applications due to its cylindrical 21700 and high power 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.
Motorsports: Demands sustained high discharge under competitive load profiles, rapid transient response for acceleration, and thermal stability to maintain performance during race conditions.
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 BAK INR2170-45D across key indicators, including constant current behaviour, rate capability, temperature dependence, and available power under representative drive cycle conditions.
Constant Current Voltage
The BAK INR2170-45D constant-current plots reveal voltage behaviour under steady loads, ideal for analysing efficiency.
Constant Current Temperature
The BAK INR2170-45D constant-current plots reveal temperature behaviour under steady loads, ideal for analysing thermal response.
Pulse Power Behaviour
The BAK INR2170-45D pulse power map evaluates short-duration load responses, allowing engineers to determine the maximum available power as a function of state of charge and temperature.
Dynamic Profile Response
The BAK INR2170-45D mission-profile plots simulate real-world duty cycles, showing how the cell manages dynamic power demands and temperature changes.
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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 BAK 45D with similar Cylindrical 21700 cells offering comparable capacity and performance characteristics.
Model
Capacity
Max Discharge
Typical Use
Access Cell Data
Manufacturer Background
BAK
BAK Battery is a Chinese lithium-ion battery manufacturer
BAK Battery is a prominent Chinese lithium-ion battery manufacturer specializing in cylindrical cells for electric vehicles, power tools, and consumer electronics. Founded in 2001, BAK produces high-quality 21700 cells with competitive energy density and cost-performance ratios. Their advanced manufacturing facilities in China supply domestic and international markets, serving major EV manufacturers and battery pack assemblers. BAK's cylindrical cell technology emphasizes safety, reliability, and scalability for mass-market applications. The company's vertical integration strategy encompasses cathode material development, cell production, and battery management systems, positioning BAK as a cost-effective solution provider in the rapidly expanding global battery market.
Frequently Asked Questions
What is the capacity and voltage of the BAK 45D?
The BAK 45D has a nominal capacity of 4.4 Ah and a nominal voltage of 3.6 V, providing 15.8 Wh of energy per cell.
What is the maximum continuous discharge capability of the BAK 45D?
The BAK 45D supports continuous discharge rates up to 60 A, delivering exceptional power density of 3,130 W/kg.
How much does the BAK 45D weigh and what is its volume?
The cell has a mass of 69 g and a volume of 25.57 cm³.
In which industries is the BAK 45D commonly used?
The BAK 45D is used across eVTOL, motorsports, drones, and e-mobility, applications that demand both high energy and power density.
What is The Voltt and how does it accelerate cell evaluation?
The Voltt is About Energy's digital cell simulation platform that models electrochemical and thermal performance, reducing evaluation time by up to 70% compared to laboratory testing.
What data can be extracted using The Voltt?
Engineers can simulate and visualise voltage, temperature, and power responses under constant-current or mission-profile conditions, generating detailed discharge plots to support accurate cell comparison and validation.
