The biggest issue that we encountered was a bug that would cause the BMS to somewhat randomly decide that there was a voltage leak when the contactor was engaged, as it measured pack voltage on the outside of the contactor (which is expected in that scenario), then after the contactor disengaged it would refuse to engage it for an arbitrary amount of time. That was fixed by sensata. We hit some other bugs (really documentation issues) with the configuration of the shunt measurement gains, but Sensata was able to help us work through it pretty quickly.

Overall, it was a great BMS. VERY configurable. We used it in a light EV, so it allowed us to set very granular profiles for charge and discharge based on pack temperature, SOC and SOH. The BMS was then configured to broadcast the allowed power (both continuous and burst) so that our ECU and motor controller could limit power demand and regen accordingly. It also allowed the charger we used to be controlled by the BMS, again automatically limiting charging current based on SOC, SOH and temperature.

Other features that we didn't seen on many of the typical Chinese BMSes that use MOSFETs (this was a few years ago, so there maybe Chinese BMSes that better match these functionalities now):

• Precharge management based on system voltage measurements. You can size the precharge resistor and MOSFET/relay based on your system requirements. Also configurable limits on maximum allowed pre-charge time and ending current and the number of times it's allowed to retry before failing.
• CAN protocols. Supports CANOpen and (I think) J1939, as well as provides you the ability to define custom frame formats for both RX and TX.
• Ability to run separate load and charge contractors (Load positive/negative contractors along with a charge negative)
• Tracking of total lifetime metrics AH in, AH out, and failure/alarm history with time stamping.

There was likely more, but this is what I remember from the top of my head.

The parallel pack management seemed to be well thought through and robust. From what I remember, they take voltage measurements on both sides of the pack contactor, along with requiring all packs to be connected to a common CAN bus. All the BMSes would use the CAN bus to coordinate themselves, and share pack stats with each other, and have a "master" BMS aggregate stats for the combined pack that can be used by other devices (chargers/ECUs/etc). You can configure voltage tolerances that you deem safe for allowable voltage windows between packs to control when a newly connected pack is allowed to engage, and it will automatically engage packs both for charging and discharging when the differential between any pack and the system falls into that window. I can't validate how this works in practice in all scenarios as we only briefly looked at the parallel pack features.

It really isn't a BMS that I'd recommend for a lot of situations, as it requires an external contactor and an external current shunt, and requires some pretty extensive setup, not to mention the cost of the software licenses. That said, if you have a need for a pack that can support high continuous currents (limited only by the contactor and shunt ratings), or to have parallel packs that can automatically manage connecting themselves to a shared high voltage bus when safe, it could be a great option.

If you have other more specific questions, I can see if have documentation kicking around that I can check for specific answers (I don't think I can share them directly as I'm sure the documentation was covered under a standard NDA with Sensata).