HHS Stackable Battery Series
EV battery supply chain development presents unique challenges due to the need for localized mining and processing of critical minerals and component parts. Regional instability, political conflict, and trade disputes may impede the global supply of these materials.
The HHS stackable battery is designed to deliver maximum energy output and capacity with ease of installation. Its modular design enables flexible expansion and capacity adjustment.
High Energy Density
In the battery sector, high energy density refers to the amount of power stored in a given volume. This is a very important measure, as it defines how long an electric car can drive on a single charge and enables longer distances between charges.
Battery development is focused on improving energy density. This includes improving the cathode materials, increasing the anode material surface area, and reducing the thickness of the separators. In addition, researchers are exploring alternative materials that can offer improved specific energy such as lithium vanadium oxide, silicon nanowires and tin nanoparticles in the anode, and composite and superlattice cathodes.
The current battery technology used in electric cars uses an integrated cell architecture where power and energy are separated, but this doesn’t provide the required level of performance and output. This has prompted research into hybrid RFBs that combine a solid state electrolyte with an integrated cell architecture. GM Ovonic and Cobasys both developed such batteries that are built using ten NiMH cells in series (as opposed to eleven in the EV-1 by GM).
However, these hybrid RFBs have lower cycling stability and rate performance and require additional devices for stack pressure. In addition, the recycling process for these types of batteries emits a significant amount of GHG. Moreover, these batteries are very expensive.
High Power Output
The Stack’d Series has been designed to handle a wide range of load scenarios, even at the highest possible current draw. It does this with the help of a 500 amp fuse under the cover. This is the same fuse used in EVs that has a 50,000 amp interrupt capability. Epoch uses this fuse to protect the battery from the high currents that might be experienced during an extremely high-load scenario.
In order to meet the demand of the electrified transportation industry, battery packs need a high working voltage. These battery HHS stackable battery packs require several hundred cells in series. BEs offer a unique solution for this issue by simplifying the cell series connection. BEs inherently reduce the required number of wires by eliminating the need for a cell connector and reducing the internal resistance of the battery. BEs also allow for a shorter electron transfer and more homogeneous current distribution, resulting in lower ohmic resistance and polarization and less heat production.
In addition to performance tuning on the battery cell level and careful analysis of the application requirements, a holistic system-level approach should be applied in order to maximize the potential of stationary storage systems. This includes the selection of suitable storage sub-components and an optimized system operation strategy. This will lead to improved energy efficiency and better profitability of stationary storage systems.
Flexible Configuration
Battery energy storage (BESS) systems are critical to enable our electricity system to harness renewables such as wind and solar, and then dispatch them when needed. Regardless of the size of a BESS, its components should be able to operate together power-storage-brick seamlessly and efficiently to provide high power outputs for the duration of the storage cycle.
The main component of a BESS is the lithium cell which is stacked and wired in series and parallel within a frame to form a module. This is then grouped into a larger number of modules to create a battery rack that can be combined with other modules to build up the required voltage and current capacity.
Most battery chemistries allow the cells to be connected in parallel to achieve higher voltages and capacities. However, the cells should be of the same make and size to avoid an imbalance. Like a chain, a battery is only as strong as its weakest link.
In addition, wearable technology applications require LIBs that can adapt to irregular shapes of the devices. Bipolar electrodes offer several advantages in this regard, including a shape-versatile design, short electron transfer for lower ohmic resistance, and homogeneous current distribution for reduced heat generation.
Intelligent BMS
The key function of a BMS is to monitor and control the battery pack (row x column matrix arrangement of batteries). Battery cells have various electrical properties that require careful oversight, including their voltages, temperature, capacity, power consumption, operating time, charging cycles, etc.
The second most important function is cell balancing to manage that adjacent battery cells throughout the stack have roughly the same state of charge (SOC) at any given point in time. This is a crucial battery performance feature that prevents general degradation over time and prevents hot spots from overcharging weaker cells in the pack.
BMS thermal management is also critical, as lithium batteries are susceptible to temperature. It is a well-known fact that when lithium batteries are charged and discharged at elevated temperatures, their performance efficiency can drop by up to 50%. Thus, the thermal management function within the BMS can ensure that a battery operates within its Goldilocks temperature range of 30 – 35degC during typical operational usage, thereby maximizing its performance and life span.
A BMS can leverage a variety of tricks to trickle heat energy into the pack and maintain a tight temperature range. For example, a BMS can turn on resident heater plates in the pack or employ power electronics to continuously cycle current through the modules to provide passive heating.
