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How to specify a 18650 Cell

What to put on an RFQ for 18650 Cell: the ratings, documents, and constraints that change the quote.

25 Oct 2026 · 3 min read · Tradinor Desk

Specification points for 18650 CellTRADINOR · FIGUREWhat to lock for 18650 CellTransportChemistryVoltage and capacityCurrent
Put these on the RFQ for 18650 Cell before you compare prices.

A buyer searching for 18650 Cell is usually trying to stop a bad substitute. A battery is specified by chemistry, voltage, capacity at a stated discharge, and the management or charger that must match it. The notes below are selection criteria for a 18650 Cell. They are not a catalog promise. Confirm every rating on the current datasheet, drawing, or test report for the revision you will receive.

What has to be true of 18650 Cell

A battery is specified by chemistry, voltage, capacity at a stated discharge, and the management or charger that must match it. For a 18650 Cell, start from the duty, then the interface to the rest of the machine or the room, then the document that proves the claim. A lower price that leaves one of those blank is a different product.

18650 Cell is easy to confuse with Battery Cooling Plate. If the quote could be read as either, add the line that separates them: the rating, the fitment, or the standard named below. Link the drawing number to that line so receiving inspection can reject the wrong one.

Numbers that change the quote

Line What to write for 18650 Cell
Transport Lithium shipments follow dangerous-goods rules. Include that in the cost.
Chemistry Lead-acid, LiFePO4, or another lithium family. Lithium is not one part.
Voltage and capacity Nominal voltage and amp-hours at a stated discharge rate.
Current Continuous and peak discharge, and maximum charge current.
Temperature Operating and charging limits. Cold charging can destroy some lithium cells.
Management Who supplies the BMS, and which charger profile is allowed.

How to compare two offers

Lay both quotes for 18650 Cell on one sheet and line up transport, chemistry, and voltage and capacity. If a cell is empty, the offer is not finished. Ask for the missing line in writing. When those match, the honest difference is lead time, the test evidence, and who carries the warranty. Do not average a fully specified 18650 Cell with a cheaper line that omitted transport.

Documents worth having before the deposit

UN 38.3 is the usual transport test for lithium cells and batteries. Ask for the pack, not only the cell. The file should name 18650 Cell and the revision, not only the supplier’s homepage. A factory quality certificate such as ISO 9001 can sit beside that file. It does not replace it.

Failures that show up after delivery

  • Using a starter battery for a deep daily cycle.
  • Reading capacity at a gentle lab discharge and expecting it at a high current.
  • Charging lithium on a lead-acid profile.

On a 18650 Cell, the expensive version of the first mistake is discovering it after the goods are in the crate. Put the rejection condition in the purchase order while the supplier can still restate the offer.

A worked RFQ line

Use this shape, then replace the brackets with your duty: “18650 Cell — Name chemistry, voltage, amp-hours, continuous current, temperature, and BMS.” That sentence is a template, not a rating of any brand. If a supplier’s datasheet uses different units, convert them onto this sheet so the next offer can be compared.

Where words like automotive grade belong

Searches often add a constraint to 18650 Cell: automotive grade, or RoHS / CE. Keep those on this page. Automotive grade is a temperature, vibration, and documentation claim. Ask which AEC or customer spec is actually met, and for which part number. RoHS is a material limit. CE is a declaration that lists the rules relied on. Ask for the document that names this part number and revision. If you need a third constraint, add it as another line on the same drawing. A second URL that only swaps the adjective does not give a buyer a second fact.

Related in this section: how to specify Battery Cooling Plate.

Questions buyers actually ask

What should an RFQ for 18650 Cell include?

Name chemistry, voltage, amp-hours, continuous current, temperature, and BMS.

Is a cheaper 18650 Cell the same part?

Only if transport, chemistry, and the documents match. A missing line is a different offer.

Do waterproof, OEM, or IP words need their own page?

No. For 18650 Cell they are extra lines on this specification. Ask for the test or the drawing that gives the word a value.