The most useful first package is usually modest: a product description, target market, intended operating conditions, available CAD or drawings, material assumptions and any prior test reports.
State the decision
Are you selecting a design, evaluating a supplier, planning a physical test or responding to a market requirement? The answer determines which evidence is relevant.
Describe the sample context
Cell chemistry and format, module architecture, enclosure, cooling route and venting concept can materially change the test plan.
Document prior results
Reports are most useful when the method, sample state, instrument, boundary conditions and raw-data availability are clear. A headline result alone is difficult to compare.