Thank you for your bug report! I'll investigate the biomass-barter issues!
As for the 2x2 batteries, each POIs have their own loot-pools! between version 1.0.2 and 1.1.0 I've altered the loot-pool for POIs to favor spawning more Scrap and Carcasses. 2x2 Batteries have a spawn chance of 3% in Wrecks, and 4% in ruins...
I apologize if the balance change affected your experience!