Soft Graphite Battery Felt – High Efficiency, Low Internal Resistance

Good conductivity, high temperature resistance.
Good electrochemical activity.
Reduced the cyclic degradation of the power stack.

4 unfolded soft graphite battery felt samples are displayed.

Description

Soft graphite battery felt, as a premium electrode material for energy storage systems such as vanadium redox flow batteries (VRFB), utilizes specialized fibers and weaving techniques to achieve high liquid absorption and excellent electrical efficiency.

In practical applications, soft graphite battery felt is often used together with composite flexible graphite bipolar plates in VRFB systems, forming a complementary electrode and conductive structure. Due to continuous production processing, it exhibits unique characteristics, including a smooth and flat surface, uniform thickness, and overall electrochemical consistency. As an electrode material, it delivers reliable performance in VRFB stacks, featuring low internal resistance, uniform electrochemical activity, good corrosion resistance, slow degradation over multiple cycles, and high energy efficiency.

Features

Good conductivity.
Low resistivity ensures efficient electron transport, improving battery charge and discharge efficiency.
High energy conversion efficiency.
High-purity materials reduce energy loss and improve overall energy utilization.
Excellent electrochemical activity.
High surface activity enhances the rate of redox reactions, increasing battery power density.
Strong corrosion resistance.
It remains stable in strong acid and strong alkali electrolyte environments, making it an ideal electrode material for flow batteries.
Low cycle decay.
It maintains stable electrochemical performance after long-term use, extending the service life of the battery stack.
Excellent high-temperature resistance.
It can operate for extended periods in high-temperature environments without decomposing or deforming, suitable for high-temperature electrochemical applications.

Specifications

Table 1: Soft Graphite BATTERY FELT SPECIFICATIONS
Name	Unit		Model 1	Model 2	Model 3	Model 4	Model 5	Model 6	Remarks
Thickness	mm		2.5 ± 7.5%	4.35 ± 7.5%	5.0 ± 7.5%	5.5 ± 7.5%	6.0 ± 7.5%	6.4 ± 7.5%	Customizable upon request
Density	g/cm³		0.08 – 0.11
Width	m		1.42 – 1.45
Length	m		Approx. 190/roll	Approx. 90/roll	Approx. 85/roll		Approx. 70/roll
Tensile strength	Radial	N/mm	≥ 0.1	≥ 0.15
Tensile strength	Weft	N/mm	≥ 0.08	≥ 0.18
Elongation at break	Radial	%	11	12	15	18	16	16
Elongation at break	Weft	%	17	14	22	19	17	18
Thermal conductivity (1400 °C)	Vertical	W/m ·k	0.28
Ash content	%		≤ 0.04
Volatile matter			≤ 0.06
Sulfur content			< 0.001
Iron content			≤ 0.002
Sheet resistance	Ω/□		0.2 – 0.5
Carbon content	%		≥ 99.90
Liquid retention rate	g/g		22	12	14	12	11	11
Fiber shedding rate	%		≤ 0.2
Specific surface area	m²/g		2.7 – 4.4
Note: This is just the typical value, not guaranteed value.

What is a flow battery?

A flow battery is an electrochemical device that utilizes the energy difference between specific elements' oxidation states for energy conversion. It achieves energy storage and release through redox (reduction-oxidation) reactions that occur as liquid electrolyte flows between electrodes. The used electrolyte can be pumped back into a storage tank and recirculated to the electrodes for recharging, thereby enabling the battery's reuse. The fundamental distinction between traditional batteries and flow batteries lies in their energy storage mechanisms: traditional batteries store energy within electrode materials, whereas flow batteries store energy in the electrolyte.

The detailed working principle image of a flow battery