Cylindrical Battery Liquid Injection Machine

Cylindrical Battery Liquid Injection Machine – Dual-Station Vacuum Electrolyte Filler for 21700/26650/32650

This Cylindrical Battery Liquid Injection Machine is a precision automated system designed for vacuum-assisted electrolyte filling of cylindrical lithium-ion batteries. It features a dual-station configuration for efficient processing and is specifically engineered for use within glove boxes, maintaining inert atmospheres during the critical electrolyte injection step.

System Overview:

The machine consists of two main sections:

1. Internal Glove Box Components: Stainless steel/aluminum alloy frame, dual liquid injection heads with SS316 containers, automatic lifting device, precision metering pumps, and PFA plastic liquid pipes.
2. External Control Elements: PLC controller with color touch screen, pneumatic control valve assembly (SMC modules), and all control electronics. These remain outside the glove box and connect via air pipes and cables through glove box ports.

Key Features:

• Dual-Station Design: Two independent working stations for simultaneous processing, increasing throughput.
• Automatic Lifting Device: Pneumatic-controlled spring lifting mechanism positions batteries precisely under injection heads.
• Precision Metering Pumps: Model E2a-d20i plunger pumps driven by stepping motors with precision ceramic rotary valves. Injection volume up to 20ml (23.5g) with ±1% accuracy.
• Vacuum Injection Heads: SS316 containers with double pneumatic lift/double lift shut-off valve structure. Poppet valve design enables multiple vacuum/venting cycles for complete electrolyte absorption.
• Inert Atmosphere Compatible: Designed for installation inside customer-provided glove boxes, with all control elements externally located.
• PLC Touch Screen Control: User-friendly interface for programming injection parameters and sequences.
• Clean Fluid Path: All liquid-contacting pipes made of PFA plastic, ensuring chemical compatibility and purity.

Working Principle (Two-Step Vacuum Injection):

1. The battery seals against the injection head.
2. System evacuates the injection head and battery interior.
3. Poppet valve closes, isolating the battery while maintaining vacuum inside.
4. Metering pump injects precise electrolyte volume into the injection head.
5. Poppet valve opens, and vacuum draws electrolyte into the battery.
6. Process can repeat (multiple vacuum/vent cycles) to ensure complete wetting.

Working Steps:

1. Manually place two batteries on positioning trays.
2. Press foot switch to start automatic cycle:
   • Batteries descend to injection head position
   • Ascend to seal with injection head
   • Automatic liquid injection process
   • Batteries descend after completion
3. Manually remove filled batteries.
4. Place two new batteries and repeat.

Applications:

• Electrolyte filling for 21700, 26650, 32650 cylindrical cells
• Lithium-ion battery R&D and pilot production
• Small-batch manufacturing
• Glove box-based battery assembly

Technical Parameters

Required Connections Through Glove Box:

• 1 general air inlet pipe
• 1 general exhaust pipe
• 1 vacuum pipe
• 1 pressurizing air pipe (if required)