Purity 99.9% · CAS 7440-02-0 · Ni
Nickel Wire 99.9% (3N) — battery and heating grade
Battery tabs, resistance elements
Overview
Three-nines nickel, cold-drawn with tight diameter tolerance and a bright annealed surface. The standard choice for cell interconnects, tab welding and resistance heating where weld consistency matters.
Typical trace impurities
| Impurity | Typical max |
|---|---|
| C | ≤ 200 ppm |
| Fe | ≤ 300 ppm |
| Cu | ≤ 100 ppm |
| S | ≤ 30 ppm |
Indicative values. The certificate of analysis for your lot is the binding document.
Where this grade is used
- ▪Battery pack assemblers
- ▪Heating element and thermocouple makers
- ▪Electroplating anode users
Common forms
Spool, ribbon, straight lengths
Specification at a glance
| Material | Nickel Wire (Ni) |
|---|---|
| Purity | 99.9% (3N), metals basis |
| CAS | 7440-02-0 |
| Production route | Cold drawn from commercial nickel 200/201 rod |
| Available forms | Spool, ribbon, straight lengths |
| Analysis method | ICP-OES assay plus oxygen determination |
| Documentation | Certificate of analysis per lot, RoHS and REACH statements, country of origin |
| Typical packaging | 100 g spool · 1 kg spool · 5 kg spool · Bulk drum (25 kg+) |
What 99.9% (3N) actually means
3N is shorthand for 99.9% purity on a metals basis: at most 0.1% of the material, by weight, is something other than Ni. The metals-basis convention excludes dissolved gases and, for powders, surface oxygen — which is why oxygen is quoted separately in the trace table below.
Two lots at the same nominal purity are not interchangeable if the residual elements differ. For this grade the limiting element is typically C at ≤ 200 ppm. What matters is which impurities your process is sensitive to — judge a lot on its full trace analysis, not on the headline number.
Choosing 3N versus the neighbouring grades
Coming from 99.5% (2N5): the step up buys you tighter trace control for battery tabs, resistance elements. If your process tolerates the residuals of 2N5, the lower grade remains the more economical and more widely available choice.
Going up to 99.98% (3N8) is worth it when vacuum devices, precision electronics describes your application; expect a materially higher cost per kilo and scarcer availability for a difference few processes can detect otherwise.
When in doubt, qualify both adjacent grades on a sample and run your own incoming inspection before committing a process to either.
Quality control and traceability
Nickel Wire at 99.9% is normally released against a lot-specific certificate of analysis stating the assay, the trace elements measured and the method used (ICP-OES assay plus oxygen determination). Well-run lots stay traceable from the refinery batch through to the container that reaches the laboratory.
- ▪A retained sample per lot, so a later question can be re-tested against the original material
- ▪Independent third-party verification, used when the assay is contractually critical
- ▪Incoming inspection on the receiving side — the certificate states the method, not the result you will measure
Handling, storage and shipping
- ▪Spools ship in sealed polyethylene with desiccant; leave the wire on its spool until use to protect the drawn surface.
- ▪Handle bright-annealed wire with clean gloves — fingerprints bake into a visible stain during welding or vacuum bake-out.
- ▪Nickel is not classified as flammable, but fine dust from grinding must be collected; observe local limits for nickel exposure.
Frequently asked questions
Common questions from buyers specifying nickel wire at 99.9%.
- Is 99.9% nickel wire the right grade for my application?
- It is the usual choice for battery tabs, resistance elements. Below it, 99.5% (2N5) covers less demanding work at lower cost. Above it, 99.98% (3N8) is reserved for vacuum devices, precision electronics.
- What does the 3N designation mean?
- The N notation counts the nines in the assay: 3N equals 99.9% Ni on a metals basis, with the balance made up of the trace elements listed in the analysis table.
- Which impurities are measured and reported?
- ICP-OES assay plus oxygen determination is used, and a certificate of analysis reports each element in the table above, starting with C at ≤ 200 ppm. The scope of a scan can be widened to further elements when a process is sensitive to one in particular.
- How is this grade normally packed?
- 100 g spool, 1 kg spool, 5 kg spool, Bulk drum (25 kg+). Handle bright-annealed wire with clean gloves — fingerprints bake into a visible stain during welding or vacuum bake-out.
- Which forms is 99.9% nickel wire available in?
- Commonly: spool, ribbon, straight lengths. The form is often a bigger practical constraint than the assay itself, because the last processing step has to preserve the purity already achieved.