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FoxESS Sub LFP Stakable Batteries with full capacity 3.975kWh - CS4000 ( 30-218-20103-00 )

FoxESS Sub LFP Stakable Batteries with full capacity 3.975kWh - CS4000 ( 30-218-20103-00 ) | Portlandia Electric Supply

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FoxESS Sub LFP Stakable Batteries with full capacity 3.975kWh - CS4000 ( 30-218-20103-00 )

$1,843.00 USD

$ $1,843.00 USD

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9+ sold

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We offer several ways to pay to make getting your solar kit simple:

Credit Card: if the purchase is greater than your card’s limit, you can split the cost onto multiple cards as well as Paypal, financing through Affirm, and ACH/bank transfer

You can arrange financing during the checkout process, or scroll further down this page for more details. Please note, if you'd like to finance your order, you can do so instantly, right at checkout.

How does your Lifetime Customer Support work?

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FoxESS CS4000 battery — 3.97 kWh high-voltage LFP sub module

FoxESS Sub LFP Stakable Batteries – CS4000 are engineered to provide reliable and scalable energy storage for residential and light commercial use. These batteries feature advanced lithium iron phosphate (LFP) technology, which ensures enhanced safety and consistent performance. Ideal for solar self-consumption and backup power, this system offers a flexible, future-ready energy solution.

The FoxESS Sub LFP Stakable Batteries with full capacity 3.975kWh – CS4000 ( 30-218-20103-00 ) feature a modular design. This allows users to expand storage capacity easily as their energy needs increase, without replacing the entire system.

FoxESS CS4000 battery is the slave/sub module of the ECS4000 stack. It pairs with the CM4000 master, with each CS module adding about 3.97 kWh, creating a plug-and-play series stack.

Key features

FoxESS CS4000 battery offers CAN-based BMS communication, ≥6000 cycles at 90% DoD, IP65-rated outdoor enclosure, and 50 A charge/discharge capability. This makes it perfect for clean and scalable installations with FoxESS H1 hybrid inverters. ^{[manual/datasheet]}

Energy: 3.97 kWh (57.6 V, 69 Ah); voltage range 48.6–65.7 V
Current: 50 A continuous (charge/discharge), 65 A peak (60 s)
Stacks: 1 CM + 1–6 CS ⇒ 7.95–27.8 kWh · 115.2–403.2 V nominal
Ingress & environment: IP65 · charge 0–55 °C · discharge −10–55 °C
Certifications: UL1973 · UL9540 · UL9540A · UN38.3

Specifications

**FoxESS CS4000 battery** — specification box
Module (CS4000)
Chemistry	LiFePO₄ prismatic cells
Nominal energy / voltage / capacity	3.97 kWh · 57.6 V · 69 Ah
Voltage range	48.6–65.7 V
Charge / discharge current	50 A continuous · 65 A (60 s) peak
Dimensions (L × W × H)	570 × 380 × 155 mm (≈22.44″ × 14.96″ × 6.10″)
Weight	≈35 kg (≈77 lb)
Interfaces	CAN BMS; LED status
Ingress / warranty	IP65 · 12.5-year limited
System (ECS4000 stack examples)
H2 (1 CM + 1 CS)	7.95 kWh · 115.2 V (97.2–131.4 V)
H3 (1 CM + 2 CS)	11.92 kWh · 172.8 V (145.8–197.1 V)
H4 (1 CM + 3 CS)	15.90 kWh · 230.4 V (194.4–262.8 V)
H5/H6/H7	19.87 / 23.85 / 27.82 kWh · 288 / 345.6 / 403.2 V

For residential backup, TOU shifting, and hybrid PV stacks, the FoxESS CS4000 battery acts as a rugged, scalable building block. Expansion is seamless with the CM4000 master.

Why Choose FoxESS Sub LFP Stakable Batteries - CS4000?

Energy storage is essential today for independence and efficiency. These FoxESS Sub LFP Stakable Batteries - CS4000 are built for precision and reliability to meet these evolving needs.

Full Usable Capacity for Maximum Efficiency

Unlike typical batteries that limit usable energy, the CS4000 delivers 100% usable capacity from its 3.975 kWh storage. This ensures maximum energy availability for better system efficiency.

Advanced LFP Battery Technology

Lithium Iron Phosphate chemistry offers superior thermal stability and longer life cycles. The system includes:

Improved safety with reduced overheating risks
Extended cycle life for reliable performance
Consistent power output through cycles

These advantages make the battery ideal for long-term energy storage needs.

Modular & Stackable Design for Scalable Power

Easily Expandable Energy Storage

The stackable design allows easy addition of battery modules, boosting capacity vertically without complex rewiring or extra floor space.

This modularity suits:

Homes planning solar expansions
Growing commercial energy needs
Flexible backup systems

Space-Efficient and Clean Installation

The compact form fits well into garages, utility rooms, or cabinets. This setup saves space and eases maintenance and system upgrades.

Seamless Integration with Energy Systems

These batteries work with modern inverter systems, ensuring smooth communication and optimized power management. Advanced battery management systems monitor voltage, temperature, and charge status for safe operation.

Intelligent control enhances:

Battery lifespan
System reliability
Overall energy efficiency

Built for Safety, Durability, and Longevity

Safety is a core feature due to the integrated BMS that protects against overcharge, deep discharge, overheating, and shorts. Combined with robust LFP chemistry, this creates a durable system for daily use.

With thousands of cycles and low degradation, the CS4000 is a dependable energy security investment.

Ideal Applications for FoxESS Sub LFP Stakable Batteries – CS4000

This battery system suits various energy storage needs, such as:

Residential solar storage
Backup power during outages
Load shifting and peak shaving
Small commercial energy systems

Its scalable design adapts effortlessly to changing energy usage patterns.

Future-Ready Energy Storage Solution with FoxESS Sub LFP Stakable Batteries – CS4000

As energy costs rise and renewable energy use expands, dependable storage is key. The FoxESS Sub LFP Stakable Batteries - CS4000 offer a smart, safe, and scalable choice built for sustainable energy goals. They meet today's demands and anticipate future growth.

For those searching for quick meal options like jersey mike's near me, or looking for orders at subs near me or firehouse subs near me, this system offers energy that supports a lifestyle on the move.

What is your return policy?

What’s covered by your return policy?

How long will it take to receive my order?

What are your financing and payment options?

We offer several ways to pay to make getting your solar kit simple:

Credit Card: if the purchase is greater than your card’s limit, you can split the cost onto multiple cards as well as Paypal, financing through Affirm, and ACH/bank transfer

You can arrange financing during the checkout process, or scroll further down this page for more details. Please note, if you'd like to finance your order, you can do so instantly, right at checkout.

How does your Lifetime Customer Support work?

FoxESS CS4000 battery — 3.97 kWh high-voltage LFP sub module

FoxESS CS4000 battery is the slave/sub module of the ECS4000 stack. It pairs with the CM4000 master, with each CS module adding about 3.97 kWh, creating a plug-and-play series stack.

Key features

Energy: 3.97 kWh (57.6 V, 69 Ah); voltage range 48.6–65.7 V
Current: 50 A continuous (charge/discharge), 65 A peak (60 s)
Stacks: 1 CM + 1–6 CS ⇒ 7.95–27.8 kWh · 115.2–403.2 V nominal
Ingress & environment: IP65 · charge 0–55 °C · discharge −10–55 °C
Certifications: UL1973 · UL9540 · UL9540A · UN38.3

Specifications

**FoxESS CS4000 battery** — specification box
Module (CS4000)
Chemistry	LiFePO₄ prismatic cells
Nominal energy / voltage / capacity	3.97 kWh · 57.6 V · 69 Ah
Voltage range	48.6–65.7 V
Charge / discharge current	50 A continuous · 65 A (60 s) peak
Dimensions (L × W × H)	570 × 380 × 155 mm (≈22.44″ × 14.96″ × 6.10″)
Weight	≈35 kg (≈77 lb)
Interfaces	CAN BMS; LED status
Ingress / warranty	IP65 · 12.5-year limited
System (ECS4000 stack examples)
H2 (1 CM + 1 CS)	7.95 kWh · 115.2 V (97.2–131.4 V)
H3 (1 CM + 2 CS)	11.92 kWh · 172.8 V (145.8–197.1 V)
H4 (1 CM + 3 CS)	15.90 kWh · 230.4 V (194.4–262.8 V)
H5/H6/H7	19.87 / 23.85 / 27.82 kWh · 288 / 345.6 / 403.2 V

For residential backup, TOU shifting, and hybrid PV stacks, the FoxESS CS4000 battery acts as a rugged, scalable building block. Expansion is seamless with the CM4000 master.

Why Choose FoxESS Sub LFP Stakable Batteries - CS4000?

Energy storage is essential today for independence and efficiency. These FoxESS Sub LFP Stakable Batteries - CS4000 are built for precision and reliability to meet these evolving needs.

Full Usable Capacity for Maximum Efficiency

Unlike typical batteries that limit usable energy, the CS4000 delivers 100% usable capacity from its 3.975 kWh storage. This ensures maximum energy availability for better system efficiency.

Advanced LFP Battery Technology

Lithium Iron Phosphate chemistry offers superior thermal stability and longer life cycles. The system includes:

Improved safety with reduced overheating risks
Extended cycle life for reliable performance
Consistent power output through cycles

These advantages make the battery ideal for long-term energy storage needs.

Modular & Stackable Design for Scalable Power

Easily Expandable Energy Storage

The stackable design allows easy addition of battery modules, boosting capacity vertically without complex rewiring or extra floor space.

This modularity suits:

Homes planning solar expansions
Growing commercial energy needs
Flexible backup systems

Space-Efficient and Clean Installation

The compact form fits well into garages, utility rooms, or cabinets. This setup saves space and eases maintenance and system upgrades.

Seamless Integration with Energy Systems

Intelligent control enhances:

Battery lifespan
System reliability
Overall energy efficiency

Built for Safety, Durability, and Longevity

With thousands of cycles and low degradation, the CS4000 is a dependable energy security investment.

Ideal Applications for FoxESS Sub LFP Stakable Batteries – CS4000

This battery system suits various energy storage needs, such as:

Residential solar storage
Backup power during outages
Load shifting and peak shaving
Small commercial energy systems

Its scalable design adapts effortlessly to changing energy usage patterns.

Future-Ready Energy Storage Solution with FoxESS Sub LFP Stakable Batteries – CS4000

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Customer Success Stories

Troy P

EG4 off-grid base kit, Happy with my purchase.

This is the first stage of my three planned purches. I got the eg4 inverter 6000 XP base kit with six 400 watt panels and the two server rack batteries. Did a little online research and followed the instructions and it got set up without any issues. Right now I'm just running it in my garage on a single outlet and have been running dual 750 watt water distillers with it. Once I get the second inverter and a bunch more panels and batteries, I plan on attaching it to my subpanel in my house that has my lights and outlets and appliances on it. Then I'll get a soft start for my AC and blower and run it on my main panel.

Jacob B

Easy Process, Genuine Support

Trying to pick the correct solar system for your needs can be very technical and frustrating. I wanted to thank Yvhan and the Portlandia Electric supply team for their patience and helpful attitudes through multiple calls. I feel like we were able to narrow it down to what worked for me and my family. My system works great and I couldn't be happier to have picked Portlandia Electric Supply.

Patrick B

Off Grid Solar Purchase

I wanted to get an offgrid solar system for years but didn’t know where to start. I found Portlandia Electric Supply on Facebook and decided to submit a quote. Within 24 hours I had a custom proposal that was almost half the price of the companies I had previously got quotes from. My wife and I decided to order online and the kit came in a timely manner and it was an easy install. Great company to work with!

James Martin

Highly Recommend

I would like to take the time to express the outstanding service that I was provided with by Portlandia Electric Supply. They provided me with all the answers to my questions, and after reviewing our quote over the phone I felt comfortable proceeding to order my kit. It’s exactly what I needed and they were there to help us over the phone when we had questions installing it. I highly recommend others in need to choose Portlandia Electric Supply.

Brian H

Solar Kit for Mobile Work Van

As a professional videographer, I needed reliable power on the go.Portlandia Electric Supply Delta Pro and roof-mounted panels were the perfect solution. Setup was easy, and the kit included everything needed. The Delta Pro powers my cameras, lights, laptop, and a small fridge with impressive battery capacity.

Keith S

Best Tech Support

You folks have been wonderful guiding me through the ins and outs of going solar. Plus your tech guys Rod and Nelson are the absolute best. They explained all the different aspects of inverters, batteries and how to keep them in top condition. Too much more to put here… but no other company has the 100% tech support you provide for your customers!

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Great Experience

My experience with Portlandia Electric Supply has been excellent. Before the sales, they answered all my questions to assure that I got what I needed. After the sales they continued to support me with answers and help. I had a warranty issue with a unit, and it was handled as well as possible. I would recommend them to anyone looking to go solar.

Troy P

EG4 off-grid base kit, Happy with my purchase.

Jacob B

Easy Process, Genuine Support

Patrick B

Off Grid Solar Purchase

James Martin

Highly Recommend

Brian H

Solar Kit for Mobile Work Van

Keith S

Best Tech Support

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