soldering

+- [[fab-dat]] - [[fab-qc-dat]] - [[fab-PCB-dat]] - [[PCB-standards-dat]] - [[fab-soldering-dat]]

+

+# desoldering-dat

+

+- [[PSO1043-dat]] == desoldering pump

+

+- [[PSO1038-dat]] == desoldering wire (wick)

+

+- [[hot-air-station-dat]]

+

+- [[Hot-Tweezer-dat]]: These are like regular tweezers but with heated tips. They can simultaneously heat and grip small two-leaded SMD components like resistors, capacitors, and SOT packages for easy removal.

+

+

+

+

+| Feature | Desoldering Wire (Wick) | Desoldering Pump |

+| ----------------- | ------------------------------ | --------------------------------------- |

+| **Function** | Absorbs melted solder | Sucks up melted solder |

+| **Best For** | Small, precise work | Removing large amounts of solder |

+| **Ease of Use** | Requires steady hand & flux | Requires quick reaction & suction |

+| **Effectiveness** | **Good for fine traces & SMD** | **Good for through-hole components** |

+| **Messiness** | Leaves minimal residue | Can scatter solder if not used properly |

+| **Durability** | One-time use per section | Reusable multiple times |

+| **Cost** | Cheap, but needs refilling | More expensive, but reusable |

+| **Skill Level** | Easier for beginners | Requires practice to master |

+| **Item** | [[PSO1043-dat]] | [[PSO1038-dat]] |

+

+

+

+

+## mess desoldering

+

+- [[preheat-bed-dat]]

+

+

+

+

+

+## ref

+

+- [[desoldering]] - [[soldering]]

+

+

+- [[soldering-dat]] - [[tech-dat]]

+

+

+# soldering-materials-dat

+

+

+- [[solder-paste-dat]] - [[soldering-flux-dat]]

+

+

+

+

+## soldering wire

+

+Nickel, Copper, and Sandwich (For 18650/21700)

+

+| Material | Best Use Case | Pros | Cons |

+| :-------------- | :--------------------------------- | :--------------------------------------------------------------------------- | :--------------------------------------------------------------------- |

+| **Pure Nickel** | Standard DIY packs (5A-15A) | Easiest to spot weld; corrosion resistant. | Higher resistance than copper; heats up at high current. |

+| **Pure Copper** | High-performance (30A+) | Lowest resistance; minimal heat generation. | Extremely difficult to spot weld (requires laser/ultrasonic). |

+| **Sandwich** | High-current DIY (Nickel + Copper) | Better conductivity than pure nickel; weldable with high-power spot welders. | Hard to tune welding parameters; risk of "cold" welds or blow-through. |

+

+

+

+---

+

+### 2. Al-Ni (Aluminum-Nickel) Composite Strips

+

+**Primary Purpose:** Transitioning between dissimilar metals.

+

+* **When to use:** Specifically for **Pouch Cells** or **Prismatic Cells** where the positive terminal (tab) is made of **Aluminum**.

+* **Why:** Aluminum and Nickel do not bond well through standard spot welding.

+* **How it works:** The strip is bi-metallic (half Al, half Ni).

+ * **Al side** is welded to the battery's Aluminum tab.

+ * **Ni side** provides a weldable surface for standard nickel busbars or wires.

+* **Summary:** It is a "bridge" material, not for 18650s (which use steel/nickel caps), but for batteries with raw aluminum electrodes.

+

+

+

+

+

+

+## 18650 Interconnect Materials: Why vs. Why Not

+

+| Material | Conductivity | Weldability | Best Used For... |

+| :-------------- | :---------------- | :------------ | :----------------------------------------------------------- |

+| **Pure Nickel** | Good (~25% of Cu) | **Excellent** | Standard DIY packs, Robotics (Rover V2), Electric bikes. |

+| **Pure Copper** | **Best (100%)** | **Very Poor** | Ultra-high performance racing drones or EV modules. |

+| **Sandwich** | High | **Difficult** | High-current DIY builds (Copper strip under a Nickel strip). |

+

+---

+

+### Why we choose Pure Nickel for 18650s:

+1. **High Resistance (Ideal for Welding):** Spot welding relies on electrical resistance to generate heat. Nickel resists current just enough to melt instantly at the contact point, creating a strong bond.

+2. **Thermal Control:** Copper is a "heat sink"—it pulls heat away so fast that the weld point never gets hot enough to melt, but the battery cell underneath gets dangerously hot.

+3. **Corrosion Resistance:** Nickel does not rust or oxidize easily. Copper turns green (oxidizes) over time, which increases resistance and creates "hot spots."

+4. **Tool Compatibility:** Most hobbyist spot welders (Sunkko, Malectrics, Kweld) are designed specifically for the physics of nickel.

+

+

+

+## ref

+

+- [[soldering-tools-dat]]

+

+

+

+

+# solder-paste-dat

+

+- [[high-precise-printing-dat]]

+

+

+## “Solder paste should be more viscous so it doesn’t spread or drip.”

+

+- **More viscous** → thicker, stickier, flows slowly

+ → Good for solder paste — it stays where you apply it.

+

+- **Diluted** → thinned by adding liquid (like flux or solvent)

+ → Not good — it becomes too runny and won’t hold components well.

+

+

+

+

+

+## Low temperature soldering paste

+

+Low temperature soldering paste is a type of solder paste designed to melt and flow at lower temperatures than standard solder pastes. Here are its main features:

+

+- Melting Point: Typically melts between 130°C and 180°C, compared to standard lead-free solder pastes which melt around 217°C.

+- Composition: Often contains bismuth-based alloys (e.g., Sn42/Bi58) instead of traditional tin-silver-copper (SAC) alloys.

+- Applications: Ideal for temperature-sensitive components, rework, or double-sided PCB assembly where high heat could dam-Age parts.

+- Reduced Thermal Stress: Minimizes risk of warping or dam-Aging PCBs and components.

+- Energy Saving: Lower reflow oven temperatures reduce energy consumption.

+- Compatibility: Useful for mixed-technology boards or assemblies with plastic connectors and LEDs.

+

+

+

+

+### Solder Paste Types and Applications

+

+

+| Solder Paste Model | Composition | Powder Type | Application/Notes |

+| -------------------- | ------------------- | ----------- | --------------------------------------------------- |

+| Mobile Repair GY618B | Sn62.8-Pb36.8-Ag0.4 | Type 4 | For mobile phone repair |

+| A-888 | Sn63-Pb37 | Type 3 | resistors, capacitors, simple IC PCBs |

+| A-888 | Sn63-Pb37 | Type 4 | resistors, capacitors, fine-pitch/multi-pin IC PCBs |

+| SMT Chip A-888 | Sn63-Pb37 | Type 5 | resistors, capacitors, dense/multi-pin IC PCBs |

+| GY-626B | Sn62.9-Pb36.9-Ag0.2 | Type 4 | QFN type PCBs |

+| GY-618B-B | Sn62.8-Pb36.8-Ag0.4 | Type 4 | BGA pack-Age PCBs |

+| LED Chip GY361 | Sn55-Pb45 | Type 3 | LED lamps, strips, and tapes |

+| GY638A | Sn60-Pb40 | Type 3 | Performance superior to GY361 |

+

+

+

+## target

+

+- [[FPC-dat]]

+

+

+

+## Common type Solder Paste

+

+| melting point | tin content | Note |

+| ------------- | ----------- | -------------------------------------------------------------------- |

+| 138 C | 42% | ultra-low temperature, bismuth-based, for special low-temp soldering |

+| 150 C | 42% | low temperature, bismuth-based, for temperature-sensitive components |

+| 183 C | 63% | best for most common PCB, small spacing, high parts density |

+| 217 C | 99.3% | lead-free, SAC305 alloy, standard for RoHS compliant PCBs |

+

+

+

+

+

+

+

+

+

+

+

+

+## solder paste printer

+

+

+

+

+

+## ref

+

+- [[solder-paste]]

+

+- [[soldering-dat]]

+

+# soldering-flux-dat

+

+

+

+- helogen free == white

+

+

+环保助焊松香

+- 易焊锡

+- 防氧化

+- 无腐蚀性

+- 无铅环保

+- 绝缘阻抗高

+- 浸润性好

+

+

+## ref

+

+- [[soldering-tools-dat]]

+# fab-soldering-dat

+

+- [[PCB-soldering-skills-dat]]

+

+- [[PCB-desoldering-dat]]

+

+- [[PCB-soldering-dross-dat]]

+

+- [[PCB-soldering-tools-dat]] - [[soldering-tools-spot-welding-dat]] - [[soldering-iron-dat]] - [[preheat-bed-dat]] - [[hot-air-station-dat]]

+

+

+- [[soldering-materials-dat]] - [[soldering-flux-dat]] - [[solder-paste-dat]]

+

+

+

+

+## ref

+

+