Pre-Cut Nickel Strips for Battery Rebuilds: Which Set Fits Your Pack?
Pre-Cut Nickel Strips for Battery Rebuilds: Which Set Fits Your Pack?
Cutting your own nickel is not hard. Cutting sixteen identical pieces, square, burr-free, to the millimetre, at eleven at night, with a spot welder already warm — that is the part people underestimate.
This guide covers when pre-cut sets are worth it, the difference between strips and busbars, why some sets are copper, and which set matches your pack.
If you are still deciding on thickness and width, start with our nickel strip sizing guide — it works through the current calculations. This guide assumes you already know your size and are choosing a form factor.
Pre-cut or off the roll?
Roll is cheaper per inch and it always will be. The question is what your time and consistency are worth.
| Roll | Pre-cut set | |
|---|---|---|
| Cost per pack | Lower | Higher |
| Prep time | 30–60 min measuring and cutting | None |
| Consistency | Depends on your shears and patience | Identical every time |
| Best for | Custom packs, odd geometries, volume | Known pack platforms, one-off rebuilds |
Roll wins if you are building something custom, rebuilding the same platform repeatedly at volume, or you already own good shears and a template.
Pre-cut wins if you are rebuilding a known pack once or twice. The set costs a few dollars more than the nickel it contains, and it removes the step where a slightly-off strip bridges two cells it should not.
There is a quality argument as well. Hand-cut nickel carries burrs along the sheared edge, and a burr sitting against a cell wrapper is a slow puncture waiting to happen. Pre-cut sets arrive deburred.
Strips or busbars?
Both join cells. They differ in how much of the pack they cover at once.
Strips are individual pieces — you place one per joint. More placements, more welds, more chances to misalign, but total freedom over layout.
Busbars are single shaped pieces that span a whole parallel group or an entire series junction in one part. Fewer pieces to handle, alignment largely solved by the shape itself, and lower resistance because the current path is one continuous piece of metal rather than several welded together.
For high-current 21700 packs, busbars are the better engineering answer. For older 18650 tool packs, strips are usually what the original layout used.
Why some sets are copper
This is the part that confuses people, and it is worth understanding before you spend the extra money.
Copper carries roughly four times the current of pure nickel for the same cross-section. On a high-drain pack that means less heat, less voltage sag under load, and more of your cells' actual capability reaching the tool.
So why is anything made of nickel at all?
Because copper will not spot weld to a cell. A spot weld forms because the joint resists current and heats at exactly that point. Copper conducts so well that the welding current passes straight through without concentrating — no heat, no nugget, no weld. Nickel's higher resistance is precisely what makes it weldable.
The solution is a hybrid: a copper busbar carrying the current, with nickel pads at the points that touch the cells. You weld the nickel, the current travels through the copper.
Worth it when: your pack sees sustained high current — 21700 high-drain builds, 8.0Ah and above, tools that stall under load like grinders and circular saws.
Not worth it when: you are rebuilding a drill or driver pack. Pure nickel is fine and the money is better spent on cells.
Here is that comparison on the same pack — both fit a Milwaukee M18 8.0Ah 21700:
Which set fits your pack
Fitment is not just about cell chemistry — it follows the pack's series and parallel layout. A 5S2P and a 5S3P pack of the same brand use completely different nickel geometry, because the second has an extra cell in every group to bridge.
| Pack | Layout | Cells | Set |
|---|---|---|---|
| Milwaukee M18 5.0 / 6.0Ah | 5S2P | 10 × 18650 | PC104 – $10.99 |
| Milwaukee M18 9.0Ah HD | 5S3P | 15 × 18650 | PC110 – $12.99 |
| Milwaukee M18 8.0Ah | 5S2P | 10 × 21700 | PC105 – $9.99 · PC108 copper – $16.99 |
| Makita 18V LXT | 5S2P | 10 × 21700 | PC109 – $11.99 |
| DeWalt DCB240 4.0Ah | 5S1P | 5 × 21700 | PC111 – $10.99 |
| DeWalt DCB612 FlexVolt | 15-cell | 15 × 21700 | PC101 – $11.99 |
| Ryobi 18V | 5S2P | 10 × 18650 | PC107 – $9.99 |
The two best-stocked sets, if you want to see them properly:
Welding pre-cut sets
Same technique as strip off a roll, with two adjustments.
Thicker material needs more energy. A busbar set is usually heavier than the strip you would have cut yourself, so settings that worked on 0.15mm will under-weld 0.20mm. Test on a scrap cell before committing to the pack.
Copper-backed sets weld only on the nickel pads. Place your electrodes on the pad, not on the copper. Landing on copper gets you a spark, a mark, and no weld.
Everything else holds: two pulses per joint, and tug-test each one. A good weld tears the metal before it releases the cell.
When a pre-cut set is the wrong answer
- Your pack is not on the list. Fitment is geometry — a set for a different layout will not adapt.
- You are building something custom. Roll and shears, every time.
- You rebuild the same pack in volume. Make a template and buy roll; the maths flips quickly.
For those cases, generic pre-cut strip splits the difference — consistent pieces, no fixed layout:
Related reading
- What nickel strip size do you need? The complete sizing guide
- How to rebuild a DeWalt DCB205 20V MAX 5.0Ah pack (5S2P, 18650)
- Why every 18V brand uses the 5S2P layout
- 21700 vs 18650: differences and when to use each
- Why rebuilding tool batteries beats buying new
Browse everything in our conductive strips and bus materials collection.
Fitment is based on standard pack layouts and manufacturers do revise designs across production runs — check your own pack before welding. Lithium cells store enough energy to cause serious injury if shorted. Work on a non-conductive surface and never solder directly to a cell can.
