Mold for terminals from the manufacturer: prices, catalog
2026-09-13
Mold for terminals: selection criteria and impact on the quality of battery connections
In the production of lead-acid and lithium batteries, the reliability of electrical contact is a fundamental parameter that determines the service life of the product and operational safety. The key element that ensures this contact is the terminal, the quality of which directly depends on the precision of manufacture and the properties of the usedterminal molds. Errors in the design or manufacture of the injection mold lead to the appearance of micropores, uneven crystallization of the alloy and geometric deviations, which subsequently causes an increase in contact resistance, local overheating and potential battery failure.
For manufacturing engineers and industrial equipment buyers, understanding mold design goes beyond simple tooling costs. It is a matter of ensuring the stability of the production process. This article discusses the technical aspects of designing molds for injection molding terminals, the effect of die materials on wear resistance, and the economic factors of pricing. The experience of Nanjing Qiantan Energy Storage Technology LLC, which specializes in integrated solutions for the battery industry, demonstrates how the integration of high-precision tools into the production line can minimize defects and increase the efficiency of production of traction, stationary and automotive batteries.
Technological features of injection molding of terminals
The manufacturing process of battery terminals is mainly carried out by injection molding of lead-based alloys (antimony or calcium). The mold in this process performs the function of transforming molten metal into a part with a complex geometric configuration while maintaining strict tolerances. The main technical challenges in designing such shapes are related to lead's low melting point (about 327°C) and its high density, as well as its tendency to shrink when cooled.
The design of a typical terminal mold includes several critical components:
- Gating system:must ensure laminar melt flow, avoiding turbulence, which leads to air entrapment and the formation of cavities.
- Cooling system:Uniform heat dissipation is necessary to prevent deformation of the part after removal. Uneven cooling often causes internal stress in the terminal material.
- Ejection system:Given the softness of lead alloys, ejection mechanisms must be designed so as not to leave marks or indentations on the working contact surface.
- Ventilation ducts:microchannels for gases to escape prevent casting defects such as underfilling or porosity of the structure.
Engineering practice shows that the geometry of the mold cavity must compensate for the linear expansion coefficient of the lead alloy. For different alloying additives (antimony, tin, calcium), this coefficient varies, which requires an individual approach to calculating the dimensions of the matrix. The use of universal solutions without adaptation to a specific alloy composition often leads to a mismatch between the mounting dimensions of the terminal and the battery pole terminal.
Materials of forming parts and their wear resistance
The choice of steel for making a mold determines its life and frequency of maintenance. Despite the fact that lead is a relatively soft metal, the casting process occurs under high pressure and thermal cycling. The main materials for forming inserts are tool steels of grades H13, 8407 or their analogues, which have undergone special heat treatment.
The key to durability is surface hardness and resistance to erosion. In injection molding, the melt injection speed can cause erosive wear to the entry areas of the gating system. In addition, lead alloys may contain impurities that promote abrasive wear. A quality terminal mold should withstand hundreds of thousands of casting cycles without significant loss of geometric accuracy.
Surface treatment also plays an important role. Nitriding or special coatings (such as PVD) reduce the adhesion of lead to the mold walls, facilitating demolding and reducing the need for release agents that can contaminate the terminal contact surface.
The influence of mold quality on battery performance
The geometric accuracy of the terminal obtained using a high-quality mold directly affects the parameters of the finished battery. Let's consider the main aspects of this influence:
- Transition resistance:Surface roughness and the presence of micropores increase the electrical resistance of the contact. In EV series high-power traction batteries or CP series stationary systems offered by Nanjing Qiantan Energy Storage Technology Co., Ltd., even a slight increase in resistance can lead to significant energy loss and heating.
- Unit tightness:The terminal often serves as part of the battery cover seal. Deviation in the dimensions of the seat cone or threaded part (if applicable) breaks the seal, which leads to electrolyte leakage and corrosion of the external contacts.
- Mechanical strength of connection:The porous structure resulting from poor ventilation of the mold reduces the mechanical strength of the terminal. Under vibration loads such as those found in 1S series automotive batteries or traction applications, such a terminal may break or loosen the connection.
The company's specialists, with more than 30 years of experience in the industry, note that quality control of molds is the first step in ensuring the reliability of the entire production line. The introduction of advanced technological solutions in tool design allows us to achieve the stability of parameters necessary for certification of products according to international standards.
Parameters and technical requirements for molds
When ordering or selecting a mold for the production of terminals, it is necessary to take into account a number of technical parameters. Below is a table with recommended values for standard industrial applications.
| Parameter | Recommended Value/Requirement | Note |
|---|---|---|
| Matrix material | Steel H13, 8407 (hardness 48-52 HRC) | Provides resistance to thermal shock |
| Processing accuracy | ±0.02 mm – ±0.05 mm | Depends on terminal type (threaded/cone) |
| Surface roughness | Ra 0.4 – 0.8 µm | To reduce lead adhesion |
| Number of slots | 2, 4, 8, 16 | Determined by the performance of the injection molding machine |
| Cooling system | Circulating, independent for each nest | Critical for uniformity of structure |
| Form resource | > 300,000 cycles | With proper maintenance |
| Gating system type | Cold runner or hot runner | Hot runner reduces material consumption |
It is important to note that the specific parameters depend on the model of the injection molding machine and the characteristics of the lead alloy used. Engineers of Nanjing Qiantan Energy Storage Technologies LLC, when implementing turnkey projects, conduct a detailed analysis of these parameters to optimize the production cycle of clients in Russia, Iran, Turkey and other countries of presence.
Comparison of types of mold designs
The choice of mold design depends on production volumes and product quality requirements. Let's look at two main approaches: traditional cold runner molds and modern hot runner systems.
| Characteristics | Cold runner form | Hot runner mold |
|---|---|---|
| Tool cost | Low | High (30-50% more expensive) |
| Material consumption | High (presence of sprues and flash) | Minimal (waste-free casting) |
| Casting cycle | Longer (three times for sprue cooling) | In short (fast melt feed) |
| Surface quality | Medium (possible marks from injection point) | High (even filling) |
| Service | Simple | Requires qualified service |
| Recommendation for use | Small series, prototyping | Mass production, high quality requirements |
For large manufacturers, such as partners of Nanjing Qiantan Energy Storage Technology LLC (including Tianneng and Chaowei), the use of hot runner systems is often economically justified by reducing the cost of melting waste and increasing the speed of production. However, for small quantities or specific non-standard terminals, cold runner forms remain a practical choice.
Factors in determining the price of molds for terminals
The cost of a mold is not a fixed value and depends on many factors. Understanding these factors helps buyers evaluate proposals correctly and avoid hidden costs in the future.
- Geometry complexity:Terminals with threads, internal channels or complex shapes require the use of sliders and complex ejection systems, which increases machining costs.
- Number of slots:Multi-place molds allow increased productivity, but require a more complex system for balancing melt and cooling flows.
- Quality of steel and components:The use of certified steels from European or Japanese manufacturers increases the initial price, but guarantees a predictable service life.
- Temperature control system:The integration of temperature sensors and individual cooling circuits increases the cost of the mold, but significantly increases the stability of the process.
- Engineering and design:The cost of 3D modeling and casting simulation services (Moldflow analysis) is included in the price. Failure to simulate can lead to costly rework.
Nanjing Qiantan Energy Storage Technology LLC offers a transparent pricing policy within the framework of comprehensive equipment supply projects. Thanks to global experience and partnerships with tool manufacturers, the company is able to provide competitive conditions for its customers while ensuring compliance with technical requirements.
An engineering view: typical operational errors
Even the most advanced terminal mold can fail prematurely if not used correctly. Several common mistakes can be identified from engineering practice:
No preheating.Starting casting in a cold mold causes thermal shock to the steel and rapid formation of cracks. The mold must be heated to operating temperature (usually 150-200°C) before production begins.
Use of aggressive release agents.Excessive use of lubricants makes it difficult to remove heat and leads to the accumulation of carbon deposits in the ventilation ducts, which deteriorates the quality of castings.
Ignoring routine maintenance.Regular cleaning, inspection of guides and lubrication of moving parts are necessary to maintain accurate mold closing. Neglecting these procedures leads to flash and accelerated wear.
Service support specialists from Nanjing Qiantan Energy Storage Technologies LLC recommend implementing preventative maintenance and personnel training systems, which is part of the company’s comprehensive approach to managing clients’ production assets.
Frequently asked questions (FAQ)
What is the service life of a quality lead terminal mold?
When using H13 tool steels and following casting conditions, the mold life is from 300,000 to 500,000 cycles. Actual service life depends on intensity of use and quality of maintenance.
Can one mold be used for different lead alloys?
Theoretically possible, but not recommended without reconfiguring the casting parameters. Different alloys (antimony, calcium) have different shrinkage and fluidity. To ensure accurate dimensions, adjustments to injection pressure and cooling time are required, and in some cases, replacement of the gating system.
How does the number of sockets in a mold affect the quality of the terminals?
Increasing the number of nests makes it more difficult to balance the filling of the form. If the gating system is not designed perfectly, the outer cavities may not fill as well as the central cavities, resulting in variations in part quality. Therefore, multi-place forms require more careful engineering calculations.
Is heat treatment of steel necessary for a mold?
Yes, heat treatment (hardening and tempering) is a mandatory step. It provides the necessary hardness (48-52 HRC) and toughness of the steel, allowing the form to withstand cyclic thermal and mechanical loads without cracking.
How to choose a mold supplier for battery production?
When choosing a supplier, you should pay attention to the presence of its own engineering department, the ability to conduct casting simulation, experience with similar products and the availability of service support. Nanjing Qiantan Energy Storage Technologies LLC offers an integrated approach, including not only the supply of equipment, but also its integration into the production line with subsequent technical support.
Conclusion and recommendations for choosing
The choice of terminal mold is a strategic decision that affects the cost and quality of the final product. You should not focus solely on the low initial cost of the tool. A more important criterion is the total cost of ownership, which includes mold life, scrap rate and maintenance costs.
For businesses seeking to improve the efficiency of lead-acid battery production, the optimal solution is to collaborate with partners with deep industry expertise. Nanjing Qiantan Energy Storage Technologies LLC provides not just equipment, but integrated solutions covering the entire cycle - from the design of production facilities to the delivery of finished products. Global experience in implementing projects in various climatic and regulatory regions allows the company to adapt technical solutions to the specific needs of customers.
Engineers and technologists are recommended to pay special attention to the simulation of casting processes at the mold design stage and strictly adhere to operating regulations. This will maximize the tool life and ensure consistently high quality battery terminals.
For detailed technical advice, a catalog of solutions or to discuss the terms of supply of equipment for your production, please read ourproducts and technical solutions.
