Why pay more for BLUETTI expansion batteries? I use WattCycle's plug-and-play hack cable to connect affordable third-party batteries to my Apex 300. Watch the video: youtu.be/IDQ4rfxd_ng The price comparison in this video shows $1,000+ in savings versus a B500K for the same nominal 5.12kWh of storage. Watch the two-battery setup power a roughly 1,400W load and recharge through the Apex 300, plus the compatibility checks, battery percentages, app settings and solar possibilities. Confirm the requirements for your exact model and cable with WattCycle before buying.