Our Technology
NFPP+ Sodium-ion Technology
Delivering high performance without compromising safety and stability.
The Strategic Evolution from LFP to Na-Series
Fundamental Safety
LFP batteries are fundamentally flammable and can release toxic gas including hydrogen fluoride (HF) and hydrogen cyanide (HCN). Alsym Na-series eliminates thermal runaway at the chemistry level, offering non-flammable operation that does not rely on active cooling or fire suppression.
Operating Temperature Range
LFP requires energy intensive, active cooling and heating to remain in an acceptable window. Alsym batteries maintain operations from –40C to 60C using only passive cooling – even in extreme climates.
Full Asset Utilization
While Li-ion batteries must hold a 30% charge during transport and require daily charge buffers, Alsym batteries can be safely discharged to 0% State of Charge (SoC). This delivers 100% usable energy capacity and allows the system to be shipped safely.
System Simplicity
LFP requires complex HVAC and fire-safety components that can account for 23-30% of total project costs. Alsym’s inability to enter thermal runaway and passive cooling design eliminates these “hidden” costs, significantly reducing both CapEx and OpEx.
Why chemistry selection defines battery safety and performance?
Layered metal oxide (LMO)
While offering high energy density, LMO sodium-ion batteries have fire and toxicity profiles rivaling lithium-ion. LMO batteries can enter thermal runaway and generate their own oxygen as they burn, perpetuating the reactions fueling the fire.
Prussian blue analogues (PBA)
PBAs face a risk of generating highly toxic hydrogen cyanide gas if exposed to elevated temperatures. Additionally, aqueous versions are limited by very low energy density PBAs face a risk of generating highly toxic hydrogen cyanide gas if exposed to elevated temperatures. Additionally, aqueous versions are limited by very low energy density.
Standard polyanionic (NFPP)
Standard NFPP is robust and offers good cycle life, but typically has lower energy density than LFP.
Alsym NFPP+
Alsym’s proprietary innovation takes the durability of standard NFPP and adds best-in-class energy density (250Wh/L) and nopossibility of entering thermal runaway.
Engineered for stability: The choice of NFPP
Atomic level rigidity
The NFPP cathode features a robust, rigid 3D crystal framework. This architecture maintains structural integrity over tens of thousands of cycles by creating open tunnel networks for ion transport.
Minimal volumetric change
When sodium ions move in and out, the NFPP crystal structure expands and contracts by less than 4%—one of the lowest in the industry. In contrast, lithium-ion cathodes experience 6–10% change, leading to micro-cracking and capacity to fade over time.
Thermal and chemical stability
The strong covalent bonds of the NFPP crystal lattice resist thermal decomposition more effectively than layered structures, providing a robust foundation that does not require active climate control.
Technical breakthrough: What is Alsym NFPP+?
Increased energy density
NFPP+ overcomes the energy density limitations of standard lithium-ion, maximizing power capacity without compromising safety or lifespan.
Non-flammable
Designed with superior thermal stability, the NFPP+ system is non-flammable, effectively eliminating the thermal runaway risks found in traditional lithium-ion batteries.
While pushing the boundaries of energy density and safety, NFPP+ continues to deliver all the core performance capabilities of standard NFPP.
Fundamental Safety
UL 9540a at the cell level
LFP batteries are fundamentally flammable and can release toxic gas including hydrogen fluoride (HF) and hydrogen cyanide (HCN). Alsym Na-series eliminates thermal runaway at the chemistry level, offering non-flammable operation that does not rely on active cooling or fire suppression.
Low Cost
Reduced System Cost and OpEx
Abundant raw materials and no active cooling required means Alsym Na-Series has competitive cell cost, low CapEx and significantly lower OpEx through reduced system complexity and aux power consumption.
Operating Temperature Range
-40C to 60C
LFP requires energy intensive, active cooling and heating to remain in an acceptable window. Alsym batteries maintain operations from –40C to 60C using only passive cooling – even in extreme climates.
Cycle Life
>10,000 cycles
Na-Series batteries are built to handle deep discharge, with over 10,000 cycles or 20 year service life. Robust hard carbon and stable electrodes reduce the range of mechanisms causing degradation in Li-ion batteries.
Efficiency
>95% RTE
With greater than 95% round trip efficiency, Alsym Na-Series keeps operating expenses down and revenue opportunities up. It ensures you have the performance, cost and financial returns needed for demanding Energy Storage System (ESS) projects.
Energy Density
250 Wh/L | 135 Wh/kg
Energy density matters for ESS not because of weight, but because it is a key driver of costs. Alsym’s NFPP+ batteries are designed for best-in-class energy density. They can also use the full depth of discharge without risk to the battery’s health or lifespan making 100% of the energy density usable.
Resource Abundance
1000x more abundant than lithium
Sodium is a resource more widely distributed than lithium and 1000x more abundant according to estimates, making it the optimal choice for long-term supply security.
0% State of Charge
Safe to Store and Transport
Na-Series batteries use aluminum current collectors that don’t face the same dissolution issues as the copper used in lithium-ion. Can be shipped or stored completely empty without damage, simplifying logistics.
Fast Charge and Discharge
2C | 2C
Unlike lithium, the Na-Series can charge and discharge up to 2C without impacting system service life. This enables flexibility including multiple cycles per day for greater revenue capture opportunities.
Sodium-ion Chemistries Compared
| Na-ion Type | Layered Oxide | Prussian Blue Analogues | Polyanionic (NFPP) | Alsym Na-Series NFPP+ |
|---|---|---|---|---|
| Fire Risk | ||||
| Gas Toxicity | ||||
| Cycle Life | ||||
| Energy Density |
Na-ion Type
Layered Oxide
- Fire Risk
- Gas Toxicity
- Cycle Life
- Energy Density
Prussian Blue Analogues
- Fire Risk
- Gas Toxicity
- Cycle Life
- Energy Density
Polyanionic (NFPP)
- Fire Risk
- Gas Toxicity
- Cycle Life
- Energy Density
Alsym Na-Series NFPP+
- Fire Risk
- Gas Toxicity
- Cycle Life
- Energy Density
As the energy transition accelerates, Alsym Na-Series batteries can power Energy Storage Systems (ESS) that are particularly well suited to the following industries:
Datacenters
Ensuring 24/7 uptime: Non-flammable storage for mission-critical AI workloads
Learn More
Defense
Enabling the next era of military technology and operational energy
Learn More
Residential
Indoor Installations of Energy Storage Without Space Constraints
Learn More
Utility & Municipal
Stabilizing the Modern Grid: High-Throughput Storage Without the Fire Risk