Diagram of my proposed upgrade with lithium house and AGM starter battery

[barrymac]

I currently have two banks of 4 Optima Blue top 75Ah batteries. the vessel has two yanmar diesels with 80A alternators.

After some research and confusion, I'm going to try the following setup, for each engine in a two engine setup.

I don't want to invest in upgrading alternators, and I found the Sterling BB1260 which I think can be configured to support mixed battery chemistry setups. I believe this should server to protect the alternators and charge both battery types as quickly as the alternators can manage.

I'll keep one of my old AGM batteries as a starter battery because I'm fairly sure they have plenty life left in them. I'm upgrading to lithium mostly because after adding a freezer I no longer have enough usable capacity in my 600Ah AGM bank.

The lithium batteries I'm using for the upgrade are these:
https://www.aliexpress.com/item/4001...27424c4dqShWTl

3.2V 200Ah

which will use this BMS: https://www.aliexpress.com/item/1005...27424c4dqShWTl
on each bank, one in each engine room.

Total cost of upgrade is 3221.05 Euro

632.47 for BB chargers

2588.58 for 800Ah of LiPo batteries and two BMSs

Anyone see any issues with this proposal?