塞包里天天磨，外壳磨花还低温发脆。充电宝外壳耐磨不够，容量再大也白搭。
结论先摆：充电宝外壳，耐磨低温绑一起
充电宝外壳包胶是“天天磨的件”：包里磨、手上磨。
材料要耐磨、低温不脆、阻燃——结论先给：充电宝外壳包胶用 SEBS 基 TPE 是主流；低温要求高，TPU 或复合优先。
充电宝外壳最大的坑：低温发脆，是结晶在作怪。结晶度高，低温就脆——结晶，是低温的开关。
充电宝外壳是功能件：磨花、开裂都是问题。材料选对，充电宝才耐用——功能件，别省料钱。
TPE凭啥扛磨：耐磨可加，阻燃可做
充电宝外壳包胶用 TPE 的理由：耐磨可做、阻燃可做、包胶成熟、效率高——四条合起来，适合充电宝外壳。
耐磨是核心：包里天天磨。耐磨（磨耗）数据按实际使用验——磨花，就是问题。
低温不能省：冬天发脆。低温冲击（-20℃）写进验收，结晶度高的料先筛掉——低温窗口，按使用地选。
磨一天冻它：包里摩擦、冬冻、发热
摩擦工况：包里磨、口袋磨。耐磨数据要验——磨花，都是问题。
低温工况：冬天户外。低温冲击数据要验——发脆，就是问题。
发热工况：充电发热。耐温数据要验——软化，包胶就松。
TPE还是TPU：外壳上看脆不脆
| 维度 | TPE | TPU |
|---|
| 耐磨 | 中 | 强 |
| 低温 | 可做 | 好 |
| 阻燃 | 可做 | 可做 |
| 成本 | 低 | 中高 |
| 包胶 | 成熟 | 成熟 |
| 批次 | 稳 | 稳 |
表格读法：TPU 耐磨低温好但贵；TPE 便宜、阻燃可做——主流充电宝 TPE。
高端耐低温款 TPU，常规 TPE——按定位选。
两个坑：结晶误判、耐磨造假
坑一：结晶误判。冬天一摔就裂，别只怪料脆——先查结晶度，再谈改配方。
坑二：耐磨虚标。报告写耐磨，实际磨花——耐磨按实测验收。
坑三：阻燃漏测。充电宝是电件——阻燃等级，必测。
验收三问：耐磨、低温、阻燃
三问：耐磨按什么方法、低温按多少度、阻燃按什么等级。一验：实际包内实测——三问一验，供应商底细清楚。
低温验证要先行：低温发脆，是结晶在作怪。先测低温窗口，再谈耐磨——低温，是外壳的生死线。
留样要成习惯：每批留样，耐磨低温按批次复测。批次换料先对比再放量——批次稳，客诉少。
冬天充电宝在车里能低到 -20℃，低温冲击不开裂才是真过关。 别按实验室一刀切，按北方实际使用温度定低温线。
充电宝贴着发热壳体，包胶长期受热就软化发粘。 先问清充电时表面温度，按这个温度做 70℃×1000h 耐热，无软化才放行。
包胶和硬壳不是越厚越好，厚度比失衡就两头不讨好。 太厚手感发闷，太薄跌落缓冲不足，按跌落高度定配比。
包里和钥匙摩擦的刮花，平面磨耗测不出来。 磨耗 ≤150mg 之外，再加一道钥匙刮擦看外观，别让新件就带痕。
防摔高度按实际使用定，工地两米、桌面半米。 别拿统一 0.8 米数据套所有场景，按用户真实跌落高度验收。
充电宝外壳包胶验收要点表
| 项目 | 测试方法 | 合格线 |
|---|
| 低温冲击 | -20℃ | 无开裂 |
| 耐磨 | 磨耗测试 | ≤150 mg |
| 阻燃 | 按等级 | 达标 |
| 长期耐热 | 70℃ 1000h | 无软化 |
| 批次 | 三批抽检 | 数据一致 |
充电宝外壳包胶常见问题与对策表
| 现象 | 原因 | 对策 |
|---|
| 低温开裂 | 结晶偏高 | 调结晶窗口 |
| 磨花 | 耐磨不足 | 换耐磨配方 |
| 软化 | 耐热不足 | 换耐热料 |
| 脱层 | 厚度比不当 | 调包胶厚度 |
| 刮花 | 异物摩擦 | 表面硬化 |
充电宝低温发脆是结晶在作怪，冬天放口袋先冻一冻。 SEBS 基耐低温好，冬天弯折不断才是真过，发硬发白就是预警。
外壳包胶防滑靠软硬和纹路，手汗浸渍不滑。 Shore A 70 上下，磨砂干爽不粘指纹，太粘滑就是体验杀手。
包 PC/ABS 骨架剥离力写进验收，四角摔三次不开裂。 发粘换低析出油，脱层升模温再试，别一上来就换料。
科隆客户案例：成本超标报价没竞争力，匹配基材回预算
厦门一家电子消费厂，充电宝外壳材料成本超标，报价没竞争力。科隆配合重新匹配包胶基材与加工温度，性能达标，成本回到预算线内。基材匹配对了，成本自然降——成本超标，先看体系选宽了没有。
小结
充电宝外壳的选型，低温先测，耐磨再验，结晶的账，配方来还。
总有人问：副牌料到底能不能用。
我们的回答一直没变——能用的地方很多，不能用的地方一处都不能碰。它和回料是两回事：一个是指标偏了，一个是分子链断了。
Rubbing inside the bag every day, the case gets scratched and becomes brittle at low temperatures. No matter how big the capacity is, a power bank is useless if its case isn't wear-resistant enough.
Conclusion first: the power bank casing, abrasion-resistant and low-temperature, tied together
The casing of a power bank with a rubber coating is a 'part that gets worn every day': it gets worn inside the bag and worn on the hands.
The material needs to be wear-resistant, not brittle at low temperatures, and flame-retardant — conclusion first: for charging bank housings with a rubber coating, SEBS-based TPE is mainstream; if low-temperature requirements are high, TPU or composites are preferred.
The biggest pitfall of power bank cases: they become brittle in low temperatures because of crystallization. When the degree of crystallization is high, they become brittle in the cold—crystallization acts as the switch for low temperatures.
The power bank casing is a functional component: scratching or cracking are both problems. Choosing the right material makes the power bank durable—it's a functional part, so don't skimp on material costs.
Why TPE can withstand wear: wear resistance can be added, flame retardancy can be achieved
Reasons for using TPE for the power bank casing: wear-resistant is feasible, flame-retardant is feasible, coating is mature, efficiency is high—combined, these four make it suitable for power bank casings.
Durability is key: the bag is used every day. Durability (wear) data should be verified through actual use—if it gets scuffed, that's a problem.
Low temperatures cannot be ignored: it becomes brittle in winter. Low-temperature impact (-20°C) is included in acceptance testing; materials with high crystallinity should be screened out first—low-temperature window, select according to the place of use.
Rub it for a day to freeze it: rub inside the bag, freeze in winter, generate heat
Friction conditions: lining wear, pocket wear. Abrasion data must be verified—scratches are all problems.
Low temperature conditions: Outdoors in winter. Low temperature impact data must be tested — if it becomes brittle, it's a problem.
Heat generation condition: heating during charging. Temperature resistance data needs to be verified—softening, the coating will loosen.
TPE or TPU: judging from the shell whether it's brittle
| Dimension | TPE | TPU |
|---|
| Wear-resistant | middle | Strong |
| Low temperature | Can do | Good |
| Flame retardant | Can be done | Can do |
| Cost | Low | Medium-high |
| Overmolding | Mature | Mature |
| Batch | Stable | Stable |
Table reading: TPU is wear-resistant and performs well in low temperatures but is expensive; TPE is cheap, flame-retardant, and workable — mainstream power banks use TPE.
High-end low-temperature resistant TPU, regular TPE — choose according to positioning.
Two pitfalls: misjudging crystallization and faking wear resistance
Pitfall 1: Misjudging crystallization. In winter, it cracks with just one fall—don't just blame the brittleness of the material. Check the degree of crystallization first, then discuss formula adjustments.
Pitfall 2: Misleading wear resistance. The report claims wear resistance, but in reality it gets scratched easily—wear resistance should be accepted based on actual test results.
Pitfall 3: Failure to test flame retardancy. Power banks are electrical devices — the flame retardant rating must be tested.
Three acceptance questions: wear resistance, low temperature, flame retardant
Three questions: What method for wear resistance, what temperature for low temperature, what grade for flame retardancy. One check: actually test inside the package — three questions and one check, supplier's details are clear.
Low-temperature testing must come first: brittleness at low temperatures is caused by crystallization. Measure the low-temperature window first, then talk about wear resistance—low temperature is the life-and-death line of the casing.
Making sample retention a habit: retain samples for each batch, and re-test wear resistance and low-temperature performance by batch. When changing materials between batches, compare first before scaling up — stable batches result in fewer customer complaints.
In winter, a power bank in the car can drop to -20°C, and surviving low-temperature shocks without cracking is the real test. Don't follow a one-size-fits-all laboratory standard; set the low-temperature limit based on the actual temperatures in northern regions.
The power bank is in close contact with a heat-generating case, and the adhesive coating will soften and become sticky if exposed to heat for a long time. First, check the surface temperature during charging, and then perform a heat resistance test at 70℃ for 1000 hours based on this temperature. Only if there is no softening should it be approved.
Rubber coating and hard shells are not better the thicker they are; if the thickness is unbalanced, it will be unpleasant on both ends. If it's too thick, the hand feel is stuffy; if it's too thin, the cushioning during drops is insufficient. The ratio should be determined according to the drop height.
Scratches caused by friction between the bag and keys cannot be measured on a flat surface. In addition to wear ≤150mg, add a key scratch test to check the appearance, so that the new parts don’t have marks.
The drop height should be determined based on actual use: two meters on construction sites, half a meter on tables. Do not use a uniform 0.8-meter figure for all scenarios; acceptance should be based on the user's actual drop height.
Key Points Checklist for Acceptance of Power Bank Shell Coating
| Project | Test method | Passing line |
|---|
| Low-temperature shock | -20℃ | No cracking |
| Wear-resistant | Wear test | ≤150 mg |
| Flame retardant | By level | Meet the standard |
| Long-term heat resistance | 70℃ 1000h | No softening |
| Batch | Three rounds of random inspections | Data consistency |
Common Problems and Countermeasures Table for Power Bank Case Coating
| Phenomenon | Reason | Countermeasure |
|---|
| Low-temperature cracking | Crystals are slightly high | Adjust Crystallization Window |
| frosted | Insufficient wear resistance | Change to a wear-resistant formula |
| soften | Insufficient heat resistance | Replace with heat-resistant material |
| Delamination | Improper thickness ratio | Swapping glue thickness |
| Scratch | Foreign object friction | Surface hardening |
Power banks become brittle at low temperatures because crystallization is causing it; in winter, put them in your pocket to freeze first. SEBS-based materials have good low-temperature resistance; truly surviving winter means bending without breaking, while hardening and turning white is a warning.
The outer shell is coated with rubber for anti-slip, depending on its hardness and texture; it won't slip even with sweaty hands. Around Shore A 70, matte finish keeps it dry and fingerprint-free; if it's too sticky or slippery, it ruins the experience.
Include the peel strength of the PC/ABS frame in the acceptance criteria; it should not crack when dropped on its four corners three times. If it feels sticky, switch to a low-exudation oil. If delamination occurs, increase the mold temperature and try again. Don’t change the material immediately.
Cologne Customer Case: Cost exceeded, quotes not competitive, matched base material to meet budget
An electronic consumer factory in Xiamen had the cost of power bank casing materials exceeding the standard, and the quotation was not competitive. Cologne cooperated to rematch the rubber coating substrate and processing temperature, achieving performance standards and bringing the cost back within the budget line. When the substrate matching is correct, the cost naturally decreases—if the cost exceeds the standard, first check whether the system selection was too broad.
Summary
When selecting the casing for a power bank, test for low temperature first, then check for wear resistance, settle the account for crystallization, and then return with the formula.
There are always people asking: Can secondary brand materials actually be used?
Our answer has never changed — it can be used in many places, but in places where it can't be used, not a single spot should be touched. It is different from recycled material: one has deviated indicators, the other has broken molecular chains.
