Total System Solutions

Total System Solutions

The performance, safety and cost of ownership of an energy storage system depend not only on the quality of the cell itself, but how well the other parts of the system work together in demanding environments.

We have brought together highly-skilled mechanical, electrical, thermal and software engineers, world-class manufacturing capabilities, and a powerful commitment to customer support to help create energy storage systems that help power your innovation. Through our engineering process we evaluated over 2,000 different sets of requirements from multiple industries in order to develop a robust building block with customizable features that allow optimized system solutions.

XPAND Battery Pack

Introducing the XPAND Family of Energy Storage Systems

The XPAND Modular Pack (XMP) is the core building block of XALT Energy’s state of the art Energy Storage Systems (ESS) based on XALT Energy’s world class lithium-ion cell designs. XMP is designed for use in multiple applications including hybrid and electric commercial truck, bus and heavy duty transportation; hybrid and electric marine power and propulsion, and grid and stationary applications.

XPAND Battery Pack


The XMP cores are designed to accommodate XALT’s family of 225mm cells, anticipating a wide variety of application voltages, powers, and energies. The XMP can be used individually or can be strung together in series and parallel to create large high energy and higher voltage systems.

Customizable Solutions

XPAND’s “variable bulkhead” design allows customized selections of interfaces (for example connectors, fuses) without having to redesign or retool the rest of the pack.

Advanced Thermal Management

XMP packs utilize an advanced, active liquid cooling system that maintains consistent cell temperatures throughout the pack and to respond quickly to temperature fluctuations due to ambient conditions of high cell duty cycles. No need for bulky air plenums, noisy fans, conditioned air, and costly filter maintenance. Energy efficient direct liquid cooling prolongs cell life under the most demanding cycles.

Introducing the XMOD Energy Storage System

The XPAND Module (XMOD) is XALT Energy’s ultra-high-density lithium-ion battery building block for highly-integrated Energy Storage Systems (ESS) based on XALT Energy’s world-class lithium-ion cells. XMOD was developed for use in high-voltage, high-capacity multi-module arrays housed in large enclosures to achieve an overall reduction in system mass, volume, and cost. XMOD is designed for use in heavy duty transportation vehicles like commercial trucks and buses, as well as marine and stationary applications.

Saving System Cost, Weight and Space

XMOD modules have the same core construction as the exceptionally durable XPAND battery packs, but without
the enclosure and bulkhead. The XMOD design is optimized for large systems where the integrator installs the modules in a suitable superstructure. Eliminating individual pack enclosures saves system weight and allows these industry-leading 175 Wh/kg modules to be packaged very close to each other, resulting in higher energy storage capacity in the available space. Furthermore, with the module arrays enclosed in a superstructure, high voltage connections can be made directly to the XMOD terminals, thereby eliminating the need for costly HV connector pairs.

Upgradeable, Ultra-Long Lifecycle Roadmap

The XMOD module is designed to accommodate cells in XALT’s 225mm family without the need for retooling, anticipating a wide variety of application voltage, power, and energy. This means as XALT’s cell technologies advance or modules become available for re-purposing, each XMOD can be replaced while all external interfaces remain the same.

Advanced Thermal Management

XMOD uses the same advanced, active liquid cooling system as XALT Energy’s XPAND packs, maintaining ideal cell temperatures throughout the module and responding quickly to increases in power demand or ambient temperatures. Efficient direct liquid cooling prolongs cell life under the most demanding cycle profiles, while reducing packaging volume.

Maximizing Energy without Sacrificing Volume, Weight or Safety

The XMOD111E module uses XALT’s 63Ah Ultra High Energy cells in a 2p24s architecture to provide 11.1kWh total energy. Designed for use with moderate charge and discharge rates (C/3 and 1C, respectively), XMOD111E is ideal for high energy applications requiring long usage periods between on-plug charging. Each module contains Voltage-Temperature-Balancing boards (VTBs) which measure voltages of all 24 cell pairs and internal pack temperatures, and perform cell balancing to maximize energy throughput. XMOD111E is designed for use with XALT’s Battery Disconnect Unit (BDU) and Master Control Unit (MCU). As with all modules in the XMOD and XMP families, XMOD111E is designed for use in large battery arrays to provide hundreds of kWh in demanding mobile and stationary environments.

XMOD Battery Module
XMOD Battery Modules in Enclosure

Performance  Characteristic XMP 71PXMP 76PXMP 111EXMOD 111E
XALT Lithium-ion CellAh40 HP43 HP63 UHE63 UHE
Pack ConfigurationP / S2P 24S2P 24S2P 24S2P 24S
Capacity (Rated @ C/2)Ah8086 126126
Voltage (Nominal)V88.888.888.388.3
Discharge Energy (C/2)Wh7,1047,63611,10011,100
Specific EnergyWh/Kg≥92≥99≥144≥175
Volumetric Energy DensityWh/L≥110≥118≥173≥208
Dimensions (all versions incl base)mm(W) 303 (L) 753 (H) 282(W) 303 (L) 753 (H) 282(W) 303 (L) 753 (H) 282(W) 276 (L) 720 (H) 269

Battery Management System (BMS)

The BMS is the “brains” of the XMP system providing the monitoring, balancing and safety functionality for the system.

The main job of the BMS is to maintain the Lithium-ion cells within their safe operating range regardless of the demands being placed on them. This means the ability to accurately predict operating situations that have the potential for creating over-voltage or under-voltage conditions, as well as high or low temperature conditions – then reacting quickly and safely to prevent those conditions from occurring.

Operational parameters for an NMC Graphite based XALT ESS

• Proven, AEC qualified components
• Sealed enclosure (IP67/IP69)
• Modular & flexible design – components are interchangable and auto-addressing
• Scalable 4-360 series cell groups
• Supports single cell and parallel cell groupings


• Power, SOC, and SOH prediction
• Thermal system control and interface
• Charger control interface
• CAN 2.0A, CAN 2.0B, J1939 application
• Robust 2-wire communication with 1250VDC isolation working voltage


• Passive balancing up to 5W / Cell
• High Voltage Interlock Loop (HVIL) monitoring of each battery string and the application
• Redundant contactor control features to ensure safe operation
• Supports ASIL D voltage measurement and ASIL C current measurement
• Compatible with all Li chemistries

Master Control Unit


Ideal for energy storage applications where high performance and high reliability are key to successful integration:

• Commercial bus & transportation
• Grid & stationary storage
• ISO & sub-ISO marine
• High performance / high voltage apps
• Industrial equipment
• Light rail

XPAND BMS Software Features:

• Multi-string management – for large scale systems of parallel battery strings
• Battery system performance algorithms (SOC, SOHc,SOHr, power available, optimal charging)
• High voltage interlock loop monitoring and control
• Isolation resistance measurement
• Battery usage recorder
• Functional safety features protected by SafeRTOS
• Telematics – data collection


BDU/SCU (Battery Disconnect Unit/String Control Unit)

The BDU manages individual strings of series-connected XMP subpacks through its on-board String Controller Unit (SCU), pre-charge circuit, current sensor, and contactors. For large XPAND systems of multiple parallel-connected strings, BDUs are connected in parallel.

Battery Disconnect Unit


• Compatible with 12V or 24V systems
• Isolated high voltage measurements up to 1250 VDC

• Current sensing capability -500A to +500A standard; up to ±1200A optional
• Redundant dual contactor controls ensure safe operation

• Self-addressing provides simple installation and service
• IP69 compliant (with connectors mated)

Master Control Unit (MCU)

The MCU manages multiple parallel strings (up to 24) while providing a single and simple interface to the application controller.


• Compatible with 12V or 24V systems
• Autonomously controls balancing of battery strings
• Provides autonomous addressing to individual battery strings, supporting a true modular architecture
• HV Interlock Loop (HVIL) monitoring of each battery string
• Provides collective system and diagnostic information to the application
• IP69 compliant (with connectors mated)

Master Control Unit

Master Control Unit

XPAND Rack System (XRS)

The XRS contains all battery system components, as well as coolant distribution manifolds and exhaust ventilation ducting. Each rack can contain up to two (2) strings of ten (10) sub-packs, and multiple racks can be connected in a row with exterior panels affixed to make a single, enclosed cabinet.


• XRS142 Type Approved per 2018 DNV-GL (Certificate # TAE00002YC)
• Easy to install, configure, and upgrade
• Outstanding safety and abuse tolerance
• Efficient direct liquid cooling maintains ideal cell temperatures
• IP44 compliant cabinet (with panels installed)
• Expandable to 2.66MWh with single MCU; virtually no limit with multiple MCUs

If you have questions about our Total System Solutions