Pairs only with EP900 / EP800-class
BLUETTI B500 expansion
Same-brand extra energy for the EP900 stack. Confirm live price — Bluetti listings move.
- Nominal
- 4,960 Wh
- Usable
- 4,464 Wh (90% DoD)
- Chemistry
- LFP
- IP
- IP65
- Host
- Does not run alone
Home / Companion kits
Add-ons that make a system last longer
Companion products that actually earn their keep
These are the parts that make one system last longer or start a hard motor. Prices below are manufacturer or typical Amazon snapshots from August 2026 and will move. How-to pages walk through the same kits in order.
1. Same-brand extra energy (buy these first)
ECOFLOW · ENTRY
DELTA 3 extra · $389 / $499
Pairs with DELTA 3 / Plus toward 5 kWh. Host required. Cheapest extra we can date.
Check DELTA 3 extra EcoFlow ladder →
ANKER
BP3800 expansion
3,840 Wh LFP for F3800. Anker US listed 1× at $1,699.99 when checked.
Check BP3800
ECOFLOW
DELTA Pro 3 extra · $1,899
Same-family pack. Ultra-series extra lists $2,299.
DP3 extra Ultra pack →
HOST
F3800 if you do not own one yet
The extra pack does not work alone (Anker FAQ).
F3800Do not mix Anker, EcoFlow, and Bluetti packs. Cross-brand 48 V projects are not a recommendation.
2. Recharge after day one
EcoFlow 400 W folding panel
$549 sale / $649 list. Useful in sun after a storm, not during landfall. Maybe 1–2 kWh on a clear day — fridge offset, not a house.
Check 400 W panelAnker 400 W kits
Often bundled with F3800 on Anker’s site. Same-brand cable, fewer surprises.
Anker solar3. Make the house circuits work (electrician)
Not DIY on a main panel
Inlet boxes and interlocks feed building wiring. Hire a licensed electrician. We link categories, not a single “best” SKU, because panel type varies.
EcoFlow Smart Home Panel 3
32 circuits, <20 ms switch. List $3,099. Pairs with Ultra X — this is the automatic-house add-on.
Check SHP3
EcoFlow transfer kit · $399
Simpler than SHP3. Electrician install. Also: Amazon inlet / interlock if you are not in the EcoFlow ecosystem.
Transfer kit Amazon inlets →Generator interlock kit
Panel-specific. Cheaper than a full transfer switch on many 200 A panels. Still a permit job in most cities.
Interlock kits4. Soft-starts (the well / AC companion)
A $300–$400 soft-start can matter more than jumping from a 6 kW to a 12 kW battery. Micro-Air EasyStart is the name most homeowners are quoted. One Amazon listing for EasyStart Flex 398 was $399 when we looked; confirm the model matches your compressor. Well-pump soft-starts are a different SKU — match voltage and HP.
This page is extras for the systems above — not another list of competing power stations. If a unit cannot be checked against a current manufacturer spec sheet, it does not belong here.
BLUETTI extra capacity