Has anyone here make a 18650 lithium battery Hybrid with a BMS?

no one here is smart enough to build a lithium pack and bms.

there is an aftermarket lithium pack though. not sure what cells (project lithium)

 

They're are round cell batteries made for all of em hybrids that is I see on baba all time like Tesla orig battery look like long fat double A batteries . Time you do all that you're going to have 14,500 possibly a little more so $2,100 for a lithium pack all bait made with square sales is still a lot better than the nickel metal hydride in the same shape I have seen the longer round cells in the same case as the Prius has the last two iterations go on Alibaba and you can look at several different iterations of how it's done they show pictures do they work I have no idea I bought a factory original if I wanted to charge that on the solar I imagine I could big enough solar system I can charge anything I think it's only 212 volts

 

Battery Monitor System??

 

Good guess. Close.
Battery Management System.

Imho, it's not that there are not any people here that are smart enough make/design a BMS, it's the cost, the time, and the liability of developing and selling one. Along, with the (lack of) potential profit. Imho, if there was much of a demand, there would be China-designed versions on ebay.

The complexity of a BMS can vary greatly.
For example, the wide selection and types of battery chargers, for solar cell systems.

 

Also HV battery ECU is designed for particular type of battery chemistry, it is not possible to make custom battery ECU without proprietary information held by toyota, Only option is to use "compatible" battery cells, luckily LiFePo cells are good match, popular Li-ion or Li-pol are very far from acceptable compatibility and would not survive 60A charging at few Ah capacity as they are safe with 1C charging only. Another aspect is longevity, lithium are not the best in this.