Test cell 5 is using the 5mm carbon felt cut in half then plated both sides.
Its protecting the nickel wire collector. The collector goes on top of 2.5 mm nickel coated carbon felt then the other half goes on top of the collector then active material on that and repeat for second collector.
The positive side has 0.6 grams nickel hydroxide 0.1 grams graphite.
The negative side has 0.4 grams Fe304 0.1 grams graphite and 0.1 grams sulphur.