Plastic Injection Moulded Battery Control System Case
Updated: Dec 23, 2020
It’s worthless to repetitively talk about how electrical appliances take up more and more space in our daily lives - electrification is a real boom these days. Electric scooters, robots, electric bicycles, electric cars - the list is endless. It seems only now are we beginning to see the real potential of electric vehicles. However, electrification faces one very important and still not fully solved challenge – energy storage.
"EMUS" company is taking this challenge by improving batteries’ management systems and thus extending batteries lifespan. Founded in 2010, "EMUS" company has been working on various control systems for electric vehicles. Over time, "EMUS" has become an exclusive manufacturer of lithium battery management systems.
Housing of any electronic gadget supports PCB’s and other electronic components inside, insulates and gives form, design and branding for the final product. This power management system device was not an exception – housing for new product was needed. We are glad that "Micromolds" team was able to provide "EMUS" company with full range of services for this project. We have successfully performed all stages of new product making:
Designing and prototyping
Optimizing for manufacturing
Parts production – injection moulding
Why did "EMUS" choose us?
We halved the tooling costs and time to market in respect of traditional plastic injection moulding. Our mould is 5-6 times smaller than the traditional one, has less cavities, thus it is made much faster and cost of production is significantly smaller. We also use “Babyplast 6/12” injection machine which has low running costs and is made for micro-injection moulding. We do not talk only about numbers. We have CNC milling machines and team of mechanical engineers all under one roof – thus we are able to optimize CAD designs for manufacturability, consult and save by not subcontracting other manufacturers. As expected production volumes were up to 100k pieces per year, our quotation appeared really favourable for EMUS company and we made a contract.
What were the main challenges?
In order to form PCB fixation hooks with injected plastic, lifters are usually used sliding diagonally in mould plates. This manufacturing technology is relatively complex and thus expensive. In order to keep the costs low our team of engineers used ejectors to form fixators. In this case, the work pieces had to be ejected manually. For a relatively small production volume, this method really paid off.
For making prototypes we used SLA (stereolithography) - 3D printing technology. Prototypes are manufactured in a layer by layer manner using photochemical processes by which light causes resin to solidify. A total of 3 prototypes were made to look for best functionality and design type. We selected the most suitable product design, performed minor tweaks and jumped straight away into mould making.
Material selection and mould manufacturing
Choosing the right materials for new product making is no less of importance. Most frequent choice of thermoplastic polymer for electronic housings and enclosures is ABS (Acrylonitrile butadiene styrene). It also works perfectly for plastic injection technology due to its relatively low melting point and good casting properties. ABS material also is favourable because of its low cost.
CNC milling machines were used for aluminium mould making. Aluminium moulds work just fine when production volumes do not exceed approximately 100k cycles. EDM technology (electrical discharge machining) was used to create a high-quality surface finish of the outer surface of the product. EDM technology allows to machine work pieces non-mechanically - the product is machined without mechanical force but is exposed to heat treatment, which allows to finish surfaces of complex shaped products.
Digital manufacturing is happening now
Not only have we become subcontractors for EMUS company and succeeded with this project but also we established lasting relationship by demonstrating advantages of digitalization when two modern companies work together. Sometimes we hear it called online manufacturing – this is what 4th industrial revolution is all about – minimal human intervention. We exchanged our sketches and CAD drawings online, discussed on optimization for manufacturability, also, online and final components were shipped as soon as production was finished. We did not make any physical contact with our client which made everything more automated, faster and safer if taking into account COVID-19.