What This Collection Delivers: Contact Force You Can Calculate Battery Contact Springs Collection 02 is a family of custom compression and leaf springs engineered for battery terminals in handheld dev
Battery Contact Springs Collection 02 is a family of custom compression and leaf springs engineered for battery terminals in handheld devices, power tools, and automotive electronics. Each spring is wound or stamped to a tolerance of ±0.01 mm on outer diameter and free length, with a maximum runout of 0.05 mm under full compression. We guarantee a consistent contact force of 0.8 N to 5.0 N across the working deflection range, verified by load testing at 3 points on every batch. Made in China at our 20-year-old Dongguan factory, this collection ships in 7 working days for prototypes, 15 days for production runs. No MOQ applies—order 50 pieces or 50,000.
Most battery contact failures come from two sources: material fatigue and inconsistent spring back. Standard springs lose 10-15% of their contact force after 10,000 cycles. We counter that with music wire (ASTM A228) or stainless steel 301 (1.4310), stress-relieved at 260°C for 30 minutes after forming. Our springs hold force within ±5% after 100,000 cycles, tested on a compression fatigue rig. For oxidation resistance in humid environments, we offer gold plating (0.5-1.0 µm) or nickel plating (3-5 µm) on request. The result is a spring that keeps its shape and conductivity for the life of your product.
We stock four raw materials specifically for battery contacts: 0.5 mm to 2.0 mm diameter music wire (hardness 45-50 HRC), 0.3 mm to 1.5 mm stainless steel 301 hard temper (42-48 HRC), beryllium copper C17200 (38-44 HRC) for high conductivity, and phosphor bronze C5210 (35-40 HRC) for low cost. Heat treatment is tailored to each alloy: music wire gets a low-temperature stress relief at 260°C, stainless steel gets 400°C for 20 minutes, and beryllium copper undergoes solution annealing at 790°C followed by precipitation hardening at 315°C for 2 hours. This gives you predictable elastic deformation with zero cracking, even at 180° bend radii.
| Specification | Value |
|---|---|
| Wire diameter range | 0.3 mm – 2.0 mm |
| Free length range | 2 mm – 60 mm |
| Outer diameter tolerance | ±0.01 mm |
| Free length tolerance | ±0.05 mm |
| Maximum runout under full compression | 0.05 mm |
| Hardness range | 35 – 50 HRC (by material) |
| Surface finish (Ra) | 0.4 µm (polished), 0.8 µm (as-formed) |
| Contact force range | 0.8 N – 5.0 N at 30% deflection |
| Lead time (prototype / production) | 7 / 15 working days |
| MOQ | No minimum (1 piece accepted) |
Every batch of Battery Contact Springs Collection 02 goes through a 100% dimensional check using a CNC optical comparator with 0.001 mm resolution. We also perform a 5-point load test on a digital force gauge for 10% of each batch, logging the load at 20%, 40%, 60%, 80%, and 100% of working deflection. Surface defects like pits, scratches, or burrs are flagged by a vision system that scans 360° at 200x magnification. We ship a test report with each order—you get raw data, not a certificate of compliance. If your application needs a specific force curve, send us your target values and we will tweak the coil count or wire diameter before production.
To give you a firm quote in 12 hours, provide four numbers: wire diameter, outer diameter (or inner), free length, and required contact force at a defined deflection. If you have a drawing, even a hand sketch, we can work from that. For custom shapes like cone-ended or double-tapered springs, tell us the end style and seating surface—flat ground ends are recommended for battery contacts to avoid scratching the cell. We also need the operating temperature range (standard is -40°C to +120°C) and whether you need plating. If you are unsure about material, our engineers will suggest one based on your current draw and cycle life requirement. Check our CNC cutting tool selection guide for material compatibility tips.
Most spring factories enforce a 5,000-piece minimum because tooling changeover is expensive. We run CNC coiling machines with servomotors and quick-change collets, so a single piece costs the same setup time as 1,000 pieces. That is why we accept orders from 1 piece upward. For a pilot run of 100 pieces, you pay a small setup fee of $25, which is waived if you later order 1,000 pieces within 60 days. This lets you validate your battery contact design in a real device before committing to volume. Our precision manufacturing process is identical for small and large batches—tolerance and finish do not change with quantity.
Springs are shipped in anti-static plastic tubes or trays to prevent tangling and surface damage. For plated springs, we add a desiccant pack and vacuum seal to prevent tarnish during transit. Standard delivery is via DHL or FedEx, 3-5 days to major cities in the US, EU, and Asia. For production orders, we can arrange sea freight with custom packaging—each spring individually compartmentalized if your assembly line uses automated pick-and-place. You will receive a packing list with batch numbers and a UID code for traceability back to our heat treatment furnace logs. For more on how we maintain consistency across batches, see our CNC machining tolerances guide.
No MOQ—we accept a single prototype spring, with a $25 setup fee waived on subsequent orders over 1,000 pieces within 60 days.
Yes, send us your target force at 20%, 50%, and 80% deflection, and we will adjust wire diameter and coil count to hit those values within ±5%.
All batches, regardless of size, undergo the same 100% dimensional inspection and 10% load testing, with a full test report shipped alongside your parts.
Prototypes ship in 7 working days after drawing approval; production orders take 15 working days, with expedited 48-hour service available for urgent samples.
Send your drawing or spec sheet for a firm quote within 12 hours. Email sc@bquq.com or WhatsApp +86 13713157787. We will confirm material, tolerances, and price before you commit.
| Parameter | Capability |
|---|---|
| Materials | SUS302/304/316, SWC piano wire, SWP music wire, 65Mn, phosphor bronze, beryllium copper |
| Types | Compression, extension, torsion, wire forms, battery springs, touch springs |
| Wire Diameter | 0.05 - 12.0 mm |
| Tolerance | ±0.02mm standard, ±0.01mm on request |
| Surface | Zinc plating, nickel, black oxide, passivation, shot peening |
| Machines | CNC spring coiling machines, torsion machines, wire forming machines |
| Prototype | 72 hours, no MOQ on samples |
| Inspection | Load test per batch, fatigue test data on request |
