At low potentials, aluminum reacts with lithium (alloying mechanism) and can therefore not be used as anode current collector. To the best of my knowledge, there is no similar alloying process in the presence of sodium, so aluminum can be used as anodic current collector in sodium-ion batteries.

Copper foil is recommended for both analytical studies[1] and applications, as anodes' material current collector for sodium-ion batteries. Aluminium as anodes' material current collector has some very limited use, only, in low cost sodium (initial generation, Beta testing) batteries.

1. Electrochemical Investigation of Electrolyte & Anodic Materials for Sodium Ion Batteries http://crimsonpublishers.com/rdms/pdf/RDMS.000561.pdf

Sebastian Maletti Ioannis Samaras . can we replace Aluminum or copper foil with carbon fiber paper?

Yes, Muhammad Tahir, you can also use carbon fiber. Depending on the origin of the carbon, you may have to consider an additional storage contribution, e.g. graphitic domains, which intercalate Li. Also, you might need to have a closer look on the SEI, depending on which electrolyte you use.

Dear Muhammad Tahir,

1) initially you have to test your new carbon fiber[1]. Form some Li (or Na)-half cells[2] to test your new modified current collector (carbon fiber) at low potentials' region, as if it was a new anode (virtual) electrode material.

2) Later, another set(2) of similar Li (or Na)-half cells[2] tests it should be formed in order to investigate it's (questionable?) behavior, at much higher potentials' region, e.g. as if it was a (virtually) new cathode electrode material.

1. What is the origin(s) of the your new carbon fiber(s) ?

2. https://www.researchgate.net/post/Can_someone_help_me_with_half_cell_battery_fabrication

Ioannis Samaras ,my carbon fiber paper is as bought from Sigma Aldrich. no Modification, no calcination to activate carbon fiber paper.

Its mass is 23 mg , it require high current to test it (CFP) so we can not find it contribution in li and Na storage.

A case study such as the one for an ideal (and stable) current collector (and carbon fibers[1]) as specific scope, demands, actually, very low[2] (near to zero) range of current[3] values.

1. Carbon fiber(s) as an "hypothetically good", and stable, current collector, such as like the Cu; Cu is a very good, and stable, current collector for (Li or Na) anode electrode materials, both in analytical investigation scope, and battery, cells.

2. apart side effects (electrolyte decomposition etc.).

3. as well as zero (insertion) charge capacity.

Sebastian Maletti But in the discharge process where the anode and cathode change, aluminum is at low potential !!!! What then?