Big Batteries for Home Backup

Solar Batteries for Home Backup: Choosing a Big Battery That Carries the House

Solar batteries for home backup store what your panels make during the day and release it at night or when the utility drops. In this collection "big" means 10kWh and up: enough to keep a refrigerator, well pump, furnace blower, lights and networking running through a multi-hour outage, or to power a house that has no grid at all. You will find wall-mounted units, server-rack stacks, outdoor cabinets and complete inverter-plus-battery packages.

The collection holds 54 products from EG4, Sungold Power, BigBattery, Pytes, Sol-Ark and HomeGrid. Prices run from about $1,580 for a single 5.12kWh rack module to $26,415 for a three-phase 85.8kWh off-grid system. Every battery here is 48V-class lithium unless the product title says otherwise.

How to choose solar power batteries for home use

• Usable kWh per day. A house that runs essentials only needs roughly 10 to 15kWh a day; add central air or electric heat and the figure doubles. The EG4 48V WallMount 16kWh Indoor Self-Heating Battery gives 12.86kWh recommended usable from one wall unit at from $3,400.
• Indoor or outdoor mounting. Garages and basements suit indoor units. If the only wall is outside, pick a sealed enclosure such as the EG4 PowerPro 48V 14.3kWh 280Ah LiFePO4 Battery, rated IP65 for direct outdoor installation and 8,000+ cycles.
• Expandable or fixed. If you might add heat pumps or an EV later, buy a platform that stacks. The HomeGrid Stack'd Series 48V 9.6-38.4kWh LFP Battery Bank starts at 9.6kWh and grows in 4.8kWh steps to 38.4kWh.
• Battery only or matched system. If you do not already own a hybrid inverter, a packaged solar power backup system for homes removes the compatibility guesswork. The EG4 PowerPro 12kW 28.7kWh 48V Battery Backup System pairs one 12000XP V2 inverter with two 280Ah batteries in a closed loop for from $8,685.

Popular picks in this collection

Sizing tips

• Count the kWh you need between sunsets, not the label capacity. EG4 publishes 12.86kWh usable on a 16kWh unit; plan around the usable number.
• Check the inverter's continuous rating against your largest motor. A 200A discharge battery behind a 12kW inverter starts a well pump; a single 5.12kWh module behind a small inverter may not.
• Run the Solar Kit Calculator with your appliances and ZIP code. It returns battery, inverter and panel sizes together, which is the only way to know whether 14.3kWh or 28.7kWh is the right starting point.
• Cold garages need heated cells. The indoor 314Ah EG4 is self-heating; unheated lithium will refuse to charge below freezing.
• Stay inside one brand's ecosystem. The Sol-Ark High Voltage 40kWh bank works only with the Sol-Ark 30K, and the EG4 PowerPro sets are closed-loop by design.

Frequently asked questions

How many kWh do I need for a solar backup system for home essentials? Fridge, lights, router, furnace fan and a few chargers typically use 8 to 12kWh over 24 hours. A 14.3kWh or 16kWh wall unit covers one full day; the 28.7kWh PowerPro package covers two.

Do these lithium batteries for home power backup work with my existing solar? Most do if you have or add a 48V hybrid inverter. Tell us the inverter model and we will confirm closed-loop communication before you order.

Can the battery sit outside in rain and snow? Only the units rated for it: the EG4 All-Weather series (IP65 and IP67), the Pytes outdoor cabinet (IP55) and the Sungold PowerMax outdoor line. Indoor units such as the Sol-Ark 40kWh bank are IP20.

All solar home backup systems here ship free to the mainland US from brand partner warehouses, usually within a few business days, with 30-day returns. Call us with your panel and inverter details and we will check the match before you buy.