Battery Technology Criteria for BESS (Part 1)
When most companies evaluate Battery Energy Storage Systems (BESS), the conversation often gravitates toward battery chemistry. However, it’s just one of the many factors impacting a BESS's success.
In fact, it ceases to be a long-term decision-driver thanks to Tanktwo’s technology, which allows operators to mix and match cells of different ages and chemistries or change suppliers on the fly. These groundbreaking capabilities free engineers from many existing constraints or supply chain challenges that could compromise a BESS’s performance.
While selecting the right chemistry for a specific application is still critical (and we’ll cover that soon), the ability to adapt to shifting requirements or supply chain issues means there’s more wiggle room to address other important factors to optimize solutions for long-term performance, safety, and ROI.
BESS deployment soared 53% in 2024 (Energy Storage News).
We start this two-part series with the battery chemistry conversation and how we eliminate the high-stakes (and scary/risky) decision of locking in one cell type and vendor from the get-go. Then, we’ll explore the full spectrum of criteria you should consider when selecting and implementing a BESS solution — whether you’re deploying a utility-scale installation, enabling microgrid resiliency, or adding backup power to a commercial facility.
Use the right battery chemistries for specific applications
Different battery chemistries deliver different characteristics. Here’s an overview:
LFP (Lithium Iron Phosphate) offers excellent thermal stability, long cycle life, a strong safety profile, and a lower risk of fire or thermal runaway. However, it has a lower energy density than NMC, so it’s less space-efficient.
NMC (Nickel Manganese Cobalt) has higher energy density, making it ideal for space-constrained, smaller-scale, or mobile applications. However, it’s more expensive, thermally volatile, and subject to sourcing concerns around cobalt and nickel.
Flow batteries (e.g., Vanadium Redox) have a very long cycle life (10,000+ cycles) but lower round-trip efficiency (~65–80%), high upfront costs, and bulkier systems.
Sodium-based batteries offer high energy density and tolerance for wide temperature ranges. However, they require robust thermal management and pose safety concerns due to reactivity with moisture.
Lead-acid batteries are a mature technology, but they are being phased out rapidly due to their short cycle life, poor depth-of-discharge performance, high toxicity, and space inefficiency.
Emerging and alternative chemistries like solid-state, zinc-air/zinc-bromine, aluminum-ion, iron-air, organic redox, etc., may become commercially viable someday. Tanktwo’s capabilities can set the stage for seamless adoption when the time comes.
In traditional battery engineering, choosing the right battery chemistry is critical because you’re locked into the cell type and vendor unless you invest the time and resources to go back to the drawing board and redesign the solution.
Since our software-defined battery (SDB) technology allows operators to switch out cells at any time without changing the product design or operating procedures, operators gain the flexibility to adjust battery behaviors (e.g., using a different cell type to increase surge capacity) based on operational requirements. This unique feature removes the pressure of predicting what the future of battery chemistry or shifting conditions might bring.
Meet system-level criteria in the real-world environment
Battery chemistry is just one (albeit critical) piece of the puzzle. Since our technology essentially removes most of the constraints around this consideration, product developers and operators can focus on evaluating their options through a more holistic lens: how a BESS solution integrates, operates, and scales over time.
1. Performance requirements
Different use cases require different performance profiles. When deciding performance requirements, consider power rating vs. energy capacity, operating duration (e.g., 1-2 hours vs. 8+ hours), charge/discharge rates, and other factors.
For example, a system supporting frequency regulation needs fast response and high power output, while long-duration backup or renewables smoothing requires deep energy capacity and extended discharge. You may select inverters that support fast ramp rates for power-focused needs or battery chemistries that suit specific thermal and cycling demands.
2. Site and environmental constraints
Where and how you deploy a BESS also impacts your choice of technology. Consider available space, indoor vs. outdoor installation, structural loading, ambient temperature range, and environmental exposure like dust, humidity, and flooding.
For instance, a commercial building in a city with limited ground space will likely put its BESS on the rooftop. The operator may stay within structural load limits using modular, lightweight enclosures while incorporating fire detection/suppression, thermal barriers, and UL 9540A-tested enclosure solutions to meet safety requirements.
3. Thermal management and safety
Thermal control systems (HVAC, liquid cooling, etc.) are essential for performance, longevity, and safety, especially in hotter climates or higher-energy chemistries like NMC. Your BESS should have built-in thermal sensors, BMS safeguards, fire suppression or containment systems, and intrinsic safety measures.
A BESS operating in a hot climate may be containerized with integrated liquid cooling to ensure stable temperatures even during prolonged charge/discharge cycles in extreme heat. It may also have real-time temperature monitoring to detect and isolate overheating modules.
4. Integration and interoperability
A BESS must work with your existing systems, from energy management software and inverters to grid-tied infrastructure, to ensure continuous and seamless operations. Successful integration with legacy infrastructure may also require translators, custom logic, and professional support to ensure seamless data exchange (which can drive up costs).
For example, an implementation must consider compatibility with existing EMS/SCADA, support for standard communication protocols, and integration with solar, generators, and other distributed energy resources (DERs).
5. Modularity and expandability
Energy storage needs fluctuate. A system that supports modular expansion can boost agility while saving significant costs and headaches later. It allows you to scale without a complete redesign and offers the option to add new battery racks or inverters cost-efficiently.
For instance, a BESS with a containerized, rack-based architecture can support drop-in expansion without extensive structural rework. You may also over-dimension the inverter and configure the energy management system (EMS) to accept more power storage capacity without reprogramming the logic.
6. Physical and cybersecurity
As grid-connected assets, BESS can be vulnerable to physical tampering and cyberattacks. Your solution must support the latest security best practices with secure access controls and monitoring, remote diagnostics, and more.
For example, a BESS serving critical infrastructure (e.g., a water treatment plant) should have a double-fenced perimeter monitored by motion-detection cameras with off-site alerts. The enclosure should include smart locks with badge authentication, while the digital control should have role-based access, time-stamped audit logs, and real-time tamper alerts.
>> Download our Battery Security white paper
7. Ease of maintenance and serviceability
Even the best BESS is only as good as your ability to maintain it over the long run. A solution should provide easy access to individual modules to simplify repairs and offer predictive maintenance tools and remote diagnostics.
For example, the Tanktwo Operating System (TBOS) provides a detailed dashboard and uses predictive analytics to alert operators when a cell is approaching failure. Additionally, the modular design means you can swap out problematic cells without tossing out the entire pack, lowering maintenance costs and downtime.
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Freedom from the constraints of battery chemistry and battery pack form factor enables engineers to design more cost-effective BESS solutions to meet real-world operational, financial, and safety requirements with fewer compromises.
Part two of this series will explore operational and lifecycle considerations, economic and business model factors, and future-proofing a BESS solution.
Get in touch if you need help defining criteria for a BESS solution, creating a product roadmap, or exploring incorporating cutting-edge battery technology into your product.
