Sensata Technologies’ i-BMS battery management system enables battery hot swapping, minimizing charging time for low voltage EVs

The new i-BMS Battery Management System from Sensata’s Lithium Balance product brand, acquired by Sensata earlier in the year, is a cell chemistry agnostic, compact, integrated BMS developed for the cost-optimized mass-production of applications up to 60V, such as 2-, and 3-wheelers, automated guided vehicles (AGVs), and robotics.

Hot swap functionality and parallel battery pack support allow for quick exchange of depleted batteries with fully charged batteries. Material handling vehicles, delivery vehicles, and drones returning to base to pick up a new load, can quickly swap depleted batteries for charged ones, allowing for continuous uptime. For electric motorbikes and three wheelers, instead of needing to recharge for several hours every evening, fully charged batteries can be rapidly installed in the field at battery swap stations, practically eliminating the need to wait and charge on the road and helping alleviate end-user’s concerns around charging time.

Parallel pack support allows the use of two or more battery packs in parallel. This functionality allows OEMs of 2- and 3-wheelers to have smaller battery modules, improving the safety and serviceability of the battery system. For example, if one battery cell fails while in use, the issue is isolated to that one faulty module which is easier to replace than the entire system and additional battery packs can continue to provide power.

While measuring 65 x 200 mm (2.6 x 7.9 in), the i-BMS PCB board is equipped with everything required to manage and maintain a battery system without the need for any external components, making it a convenient and cost-efficient design for mass production. All critical components are pre-integrated into the system, including a pre-charge circuit, on-board current measurement, MOSFET power switches for battery disconnect, and a DC/DC power supply. The solution features key components that are ASIL C Safety rated and include self-test capabilities for safety critical measurement circuits.

Advanced Software Helps Maximize Battery Use
The advanced algorithms in Sensata’s BMS software ensure accurate state-of-power (SOP) predictions based on cell internal resistance, voltage, and current constraints, precise state-of-charge (SOC) calculations, and (state-of-health) SOH calculated based on aging effect.

The high degree of accuracy in assessing the state of the battery allows for a more precise battery system, helping customers maximize utilization of the battery, and increase range, uptime, and performance of the vehicle. The BMS Creator configuration software allows the battery pack designer to create a unique battery setup by defining application specific BMS parameters and safety strategies, optimizing battery operation.

Other advanced software features include measurement of rate of change of temperature to predict thermal runaway, dynamical regulation of current in extreme thermal conditions, as well as advanced parameter settings for CAN communication.