Each part is separately made, then all the sub-assembly are joined together to engineering a battery pack. CMIUTA Electric Company uses original techniques in manufacturing to ensure maximum quality and performances.
Adding matching cells and to engineer the battery packs. To minimize the variability inside a battery pack and to ensure maximum quality, all the cells need to have the same weight (margins of 0.001 grams), identical voltage rated, same rank and initial charging date, from the same manufacturing batch.
The carbon-aluminum layers help with heat dissipation. Based on the thermodynamics of conduction this system helps to disperse heat equally from the core on the entire cell pack, aluminum shield and so. It’s not the high-performance solution but is optimal, and also keep the battery pack weight as low possible.
On next batteries upgrades, a (slightly) liquid-based cooling system also will be available, paired with a composite enclosure.
Cell pack. For a more compact design, translated into more energy density per unit volume and to improve mechanical and thermal performance, the battery cells are joined in “honeycomb form”.
Using a non-toxic flame retardant dielectric foam and encapsulating compound based on high-thermally conductive polyamide (PA) copolymer with great bond strength, the top/bottom of the pack and empty space between cells is filled and the battery pack is fully sealed. The cells terminals are connected by layers of pure nickel busbar (Ni 99.7%), through RSW welding equipment, according to the battery configuration and C-rate.
Wiring, safety elements and covering. Spending attention to detail, safety elements and joining parts, the rugged harnesses for external PCB/BMS, 24K gold-plated polarized connectors and shielded discharge cables are applied using a Silver-Copper-Stannum (AgCuSn) melting alloy.
The entire cell block is dielectrically isolated and surrounded by a multi-layers reinforced shield, with mechanical strength. All the covering materials are lightweight and provide a high sealing, improve thermal performance and contribute to the robustness of the battery pack.
To reduce manufacturing costs, the pack is wrapped with a hard (Black & Blue) PVC film. With this kind of covering the aesthetic appearance isn’t charming, but looks very compact and solid. However, we work hard to develop a tough and lightweight battery housing, from composite materials.
NCR18650GA. Using 250 Wh/kg cell designs with the design principles presented will enable 240 Wh/kg battery pack solution.