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LEO offers OEM design and manufacturing services

Battery Pack Design


No matter how complex the need, we offer a wide range of battery design solutions. A reliable, defect free and high quality battery pack and power solution begins at the design stage. With a mind for manufacturability, and using the best components, applying best practices and leveraging our years of experience, our focus is to meet our customers’ application needs.


At LEO, we understand that a defect free battery pack starts with a well thought out design that carefully considers and eliminates the potential for failure. With more than 30 years of experience and thousands of battery designs, we are uniquely qualified to design the highest quality battery pack for your application.



Cell Selection

Selecting the proper cell for a pack design is one of the most critical aspects affecting size, cost, performance and quality. LEO provides the latest cell technology along with in-depth specification and performance knowledge. With our global resource network, we can provide performance verification of cells and actual application load/temperature profile testing in our lab ensuring optimum performance in real world situations.


Safety Circuitry

LEO is a leader in developing circuitry to assure safety for all battery chemistries. All lithium ion (Li-ion) assemblies require (at minimum) a safety circuit with protection for over voltage, under voltage and over current, as well as temperature sensing to charge only when safe. Our engineering teams have many in-house designs to choose from as a reference for all applications. Since all applications are not equal, it is very important to design a safety circuit to match the product it is going into.



Fuel Gauging

The fuel gauge is an advanced warning system for low-charge or situations that signal the end of the device’s batteries. In battery charging and conditioning systems, discharge circuits may be used to completely discharge a battery before beginning a charging cycle. In battery calibration systems, discharge circuits may be used to determine the characteristics of batteries. For battery types such as lithium ion (Li-ion), determining the characteristics of the battery under load conditions may assist in determining battery condition as it ages. Additionally, calibration systems produce information that allows predicting performance of the battery over its service life.


Fuel gauging is a critical function of lithium ion battery pack design. Proper, accurate fuel gauging not only provides a clear input to the end-user regarding the available Relative State of Charge (RoC) but can also extend the cell cycle life in conjunction with methods to control depth of discharge and charge. In addition, advanced fuel gauging and data acquisition circuits can determine the battery characteristics under load and assist in determining the overall impact of aging.


In order to develop and implement a fuel gauge properly, accurate calibration methods must be employed. LEO has a patented design for a discharge circuit that addressed the challenges of battery calibration in environments where consistent power is often unavailable, such as in military vehicles and ambulances.


LEO also has the ability to develop a customized fuel gauge that can take into account specific customers needs and facilitate integrated authentication protocols.



Cell Balancing

Cell balancing during charge and discharge gets the most from a pack. There are two primary ways to balance cells. Resistive cell balancing reduces the charge to the cell with the highest state of charge by shunting charge around it until the remaining cells catch up. Cell balancing by charge transfer uses circuitry to move charge from one cell to another. This can actually raise the effective capacity of a battery pack beyond that of its weakest cell. However, it is more complex and costly than resistive cell balancing.


But there are downfalls to cell balancing. A significantly out-of-balance cell might be a sign of an internal problem, and that might present a safety hazard if the laggard cell is continually forced into balance with others.


The team at LEO has developed the most innovativebalancing technologies to provide our customers with the most appropriate cell balancing design solution for their applications.



Mechanical Designs

Some battery packs are installed inside the product, and only require a shrink-wrap enclosure. In other cases, battery packs are mounted externally and may serve a mechanical function, such as a handle or base for the product. Our team has experience designing battery enclosures of all types and can help you create one that will enhance the functional design of the product while assuring that the battery passes stringent shock, vibration and environmental testing required to certify the pack for shipping



Power Electronics

LEO has the capability to design full balance of plant power electronics systems for your specific product. From battery management to power systems energy conversion LEO has the capability to design and deliver full power electronic solutions