I found two nice videos to understand how shunts work for people who haven’t studied electrical circuits after school 
(I am one of them) : 1. General current sensing and 2. specifically in a BMS
1. Current sensing in general – This video by Texas Instruments explains how good quality shunts have to balance the opposing requirements of offset error & tolerance error on the one hand and power dissipation across the resistor on the other hand. They have also included a very handy price chart of shunt resistors with various shunt configurations (3 year old video)
Given that Shivalik shunts are used in high stakes applications, its probably safe to assume that the lower bound of price per shunt will be 0.5$ and the average price will more likely be closer to 1$ or more.
Combining this knowledge with @GourabPaul’s very useful posts regarding no. of shunts in ICE and EV powertrains can help roughly size the auto opportunity. Similar data on no of shunts per device, if gathered for smart meters and other electronic applications, can help size those opportunities too.
Conventional IC vehicles use a minimum 3-4 shunt based sensors. They have a 12 V power source and have an alternator to charge the battery.
For the x-EV, depending on the power train design the number of shunt sensors may increase of decrease. the current sensors are used in BMS (minimum 2), DCDC (minimum 4), Inverter (minimum 8), Brake Recuperation Machine (BRM) (minimum 2), charging circuit (minimum 2) , induction motor (minimum 6) on top of this there are additional monitoring circuits, protection circuits which can increase the number of shunt sensors in the vehicle.
As the industry is migrating from conventional IC based engine to battery based systems, the number of shunt sensors are definitely on the rise as electric power is routed in the entire system and it is split between various sub systems. The increase will also be evident in 2W and 3W segments as they migrate towards electric vehicles.
2. Functioning of a BMS along with use of shunt – While this video is mostly about how a BMS works and how active/passive cell balancing is implemented, from 2:24 – 3:58, the video explains the functioning of the fuel gauge monitor where shunt resistors are used to measure currents flowing in the system.
As an aside, one of the key players in this market, Rohm semiconductors started their journey in this space by manufacturing resistors. From there, over time, they diversified to other passive components and ICs and semiconductors. So as @rambaranwal has said across multiple posts in this thread, there is scope for Shivalik to forward integrate into larger semiconductor components in the future. It would be really helpful to understand their ambitions in this regard. Do the founders have the ambition of becoming a semiconductor giant from India or are they content with scaling up their existing verticals?
While semiconductor FABs would take time to build we already have fragmented PCB manufacturing factories and register and capacitor manufacturers in India, some of which would grab this opportunity to scale and improve their capability to support in building this eco system.
Shivalik manufactures, shunts, SMD registers along with some capacity to manufacture PCBs for defense.
Their Shunt and SMD register quality is world class and auto grade. The capability required to manufacture consumer grade components is much less than auto grade. I am sure they would be part of this opportunity looking at their relationship with top quality conscious customers they supply already.Only thing we need is management to grab this and they are just a tiny fish in big opportunity ocean.
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