I do have a sincere question. I am not too familiar with these new lithium systems but I have noticed more and more of them, especially in the #vanlife movement.
Can all these electronic components keep working in a sustained harsh environment? I am thinking hundred of kilometers of corrugated roads like we have encountered in the Australia outback, or even in Northern Quebec? Can they handle dust, vibration, and heat/cold cycle?
It seems to me like it would only take one of the controllers (as an example) to fail and the whole system would become inoperable. I can't imagine trying to find one of these components in the middle of Mozambique or Malawi. I mean just a regular old school 12V battery is often times 2 or 3 times the price in many countries (like in most of South America).
Can your engines electronics continue to work in a sustained harsh environment? You trust them without question when you drive into the backcountry, but a single failure would leave you stranded.
There is a wide variety of BMS designs. The simplest ones can be swapped in an hour, and cost less than 200$. More expensive marine grade ones use external relays etc, and have a bypass for emergency usage. In the case of my LFP battery, the BMS carries no more than 400mA, and main current control is via mechanical external relays. The BMS core logic board is protected against all foreseeable transients (except maybe lighting strike). In the event it fails, I can swap in a substitute in about 2 hours. If necessary I can also operate for a short period without BMS.
Electronics Engineers have lots of experience making durable and reliable electronics. Machine assembly has made them even more reliable. Combined with conformal coatings and conservative design margins, and they are pretty reliable.
As for reliability, the marine approach is to use two separate LFP batteries, each with its own BMS. Drop-ins like Lion Energy and BattleBorne work fine for this type of application. If for some reason they all fail somewhere remote, you can swap in a lead battery as a stopgap.