9–18 kWh

Home battery systemSolaX Power

SolaX Power ULTRA-THIN DESIGN

10–20 kWh · 3.8–7.6 kW · Lithium Ion · direct PV input · 12 configurations

UL 9540UL 1741 SBCEC listed · Oct 3, 2022

Usable energy9–18 kWh
Continuous power3.8–7.6 kW
Warranty12 years
ChemistryLithium Ion

Overview

CEC Energy Storage System List

ULTRA-THIN DESIGN: 9–18 kWh usable energy; 3.8–7.6 kW continuous; lithium ion; accepts solar panels directly (DC-coupled); 12 years warranty.

Models & configurations

CEC Energy Storage System List · 12 listings

Model	Energy	Power	Grid voltage	Round trip	CEC listed
A1-ESS-G2 {3.8kW, 10kWh}	10 kWh	3.8 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {5.0kW, 10kWh}	10 kWh	5 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {6.0kW, 10kWh}	10 kWh	6 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {7.6kW, 10kWh}	10 kWh	7.6 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {3.8kW, 15kWh}	15 kWh	3.8 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {5.0kW, 15kWh}	15 kWh	5 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {6.0kW, 15kWh}	15 kWh	6 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {7.6kW, 15kWh}	15 kWh	7.6 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {3.8kW, 20kWh}	20 kWh	3.8 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {5.0kW, 20kWh}	20 kWh	5 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {6.0kW, 20kWh}	20 kWh	6 kW	240 V	—	Oct 3, 2022
A1-ESS-G2 {7.6kW, 20kWh}	20 kWh	7.6 kW	240 V	—	Oct 3, 2022

Capacity & power

CEC Energy Storage System List

Nameplate energy (CEC)10–20 kWh
Total energy (datasheet)10–20 kWh
Usable energy9–18 kWh
Rated power (CEC)3.8–7.6 kW
Max continuous discharge (CEC)3.8–7.6 kW
Full-power discharge timeabout 1.2 h at full power
ChemistryLithium Ion
Grid connection240 V
Battery voltage range (DC)90–116 V · 135–174 V · 180–232 V

How long can it power your home?

Cali-Graf calculation

Average home load	Runtime from full
0.5 kW	≈ 18 h
1 kW	≈ 9 h
2 kW	≈ 4.5 h
3 kW	≈ 3 h
7.6 kW (full continuous power)	≈ 1.2 h

Runtime = 9 kWh usable (datasheet) ÷ load. A typical home averages 1–2 kW; air conditioning and EV charging use much more. Inverter and wiring losses shorten it.

Charging from solar in Southern California

NLR PVWatts v8 · Cali-Graf calculation · CEC Energy Storage System List

City	December	June
Los Angeles	2.8 kW	1.7 kW
Palmdale	2.6 kW	1.5 kW
Chula Vista	2.4 kW	1.7 kW
Huntington Beach	2.6 kW	1.8 kW
Riverside	2.7 kW	1.6 kW
Santa Clarita	2.7 kW	1.6 kW

Solar array size that refills the battery from empty in one average day, before the home uses any of it (NLR PVWatts v8, 20° south roof).

Direct PV inputYes

Installation & environment

CEC Energy Storage System List · SolaX Power datasheet

Enclosure typeNEMA 4X, NEMA 3R
Operating temperature−25 to 60 °C

Warranty

CEC Energy Storage System List · SolaX Power datasheet

Warranty term12 years
Rated cycle life (spec, not warranty)6,000 cycles

Safety listings

CEC Energy Storage System List

UL 9540 (energy storage system)Certified by CSA Group
Certificate date & editionJul 21, 2023 · Ed. 2 : 2020
UL 9540A (fire propagation test)Yes
Other standards on datasheetUL 1741, IEEE 1547, UL 1699B, UL 9540A, UL 9540, UL 1973, UN 38.3, FCC

UL 9540 certifies the whole storage system; UL 9540A is the fire-propagation test that fire codes ask for indoors and near walls.

California grid & code compliance

CEC Energy Storage System List

UL 1741 SB (IEEE 1547-2018)Yes
UL 1741 SA (Rule 21)Yes
CSIP (IEEE 2030.5)Yes (with conditions)
JA12 declaration (Title 24)No
CEC noteOnly capable of receiving DC input from PV module system if equipped with a hybrid inverter component.
Last CEC updateJan 12, 2026
Monitor Key Data schedulingYes

Full specifications

CEC Energy Storage System List · SolaX Power datasheet

Communicationwi-fi, rs485, cellular, can
Manufacturer websitesolaxpower.com

Compare with similar batteries

CEC Energy Storage System List

Battery	Energy	Continuous power	Chemistry	Warranty	SoCal permits
Generac PWRcell	8.6–17.1 kWh	3.4–6.7 kW	Lithium Ion	—	8
Lunar Energy LE-ESS-xxKWH	15–20 kWh	9.6 kW	Lithium Ion	—	3
Panasonic EVHB-I7-Xxx	9–18 kWh	7.6 kW	Lithium Iron	12 years	2
sonnen SCORE-Pxx	10–20 kWh	4.8 kW	Lithium Iron Phosphate	10 years	2
Qcells Q.HOME+ ESS HYB-G1	13.5 kWh	6–8.6 kW	Lithium Ion	10 years	1
EG4 Electronics PP-16/280A1-18K1-AWLL	14.3 kWh	8.7–10 kW	Lithium Iron Phosphate	10 years	—

Same segment, similar capacity; each row from the same sources.

Questions & answers

How much energy does the SolaX Power ULTRA-THIN DESIGN store?

9–18 kWh usable, per the manufacturer datasheet.

How long can the ULTRA-THIN DESIGN power a home?

About 9 hours at an average 1 kW load from a full charge (9 kWh usable); higher loads shorten it.

What warranty does the ULTRA-THIN DESIGN have?

12 years (datasheet).

Is the ULTRA-THIN DESIGN UL 9540 certified?

Yes — the CEC list shows UL 9540 certification (certified by csa group).

Sources

California Energy Commission — Energy Storage System List, data as of Oct 7, 2026. Manufacturer-reported values confirmed by CEC against certificates.
SolaX Power — manufacturer datasheet “ULTRA-THIN DESIGN A1-ESS-G2 Global: +86 571-56260008”.
NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Riverside, Santa Clarita, Chula Vista, Huntington Beach.
Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).