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Learn more on my YouTube Channel: @SolarJoeJoe

After 15+ years working in solar and battery storage—and building a ton of DIY systems—I'm finally sharing it all in video form. I post weekly videos, so be sure to subscribe!

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Explore our Customer's DIY Projects

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  • 🏕️ Michigan Off-Grid Cabin – DIY Solar + Battery Build

    🏕️ Michigan Off-Grid Cabin – DIY Solar + Batter...

    JOSEPH O'CONNOR

    Here’s a full breakdown of an off-grid energy system we helped design and troubleshoot for a cabin in Michigan. What started as a solar generator with lead-acid batteries eventually turned...

    🏕️ Michigan Off-Grid Cabin – DIY Solar + Batter...

    JOSEPH O'CONNOR

    Here’s a full breakdown of an off-grid energy system we helped design and troubleshoot for a cabin in Michigan. What started as a solar generator with lead-acid batteries eventually turned...

  • DIY Battery Pack with Sol-Ark Inverter, Whole Home Backup

    DIY Battery Pack with Sol-Ark Inverter, Whole H...

    JOSEPH O'CONNOR

    Project Details: LFP prismatic cells (REPT 280Ah) 16S2P configuration, 51.2V nominal, 560Ah (~28kWh Capacity) Nuvation BMS and custom stack switchgear – view options Compression end plates – view product Custom...

    1 comment

    DIY Battery Pack with Sol-Ark Inverter, Whole H...

    JOSEPH O'CONNOR

    Project Details: LFP prismatic cells (REPT 280Ah) 16S2P configuration, 51.2V nominal, 560Ah (~28kWh Capacity) Nuvation BMS and custom stack switchgear – view options Compression end plates – view product Custom...

    1 comment
  • RegenOasis - LAGI 2020 Fly Ranch

    The RegenOasis - LAGI 2020 Fly Ranch Entries

    JOSEPH O'CONNOR

    An oasis in the desert, the RegenOasis is a shade structure consisting of 91 solar Photovoltaic (PV) panels that also serves as a rainwater harvesting surface. The structure provides a...

    1 comment

    The RegenOasis - LAGI 2020 Fly Ranch Entries

    JOSEPH O'CONNOR

    An oasis in the desert, the RegenOasis is a shade structure consisting of 91 solar Photovoltaic (PV) panels that also serves as a rainwater harvesting surface. The structure provides a...

    1 comment
  • Electric VW Beetle

    Electric VW Beetle

    JOSEPH O'CONNOR

    Project in Bellingham, WA Nissan Leaf Gen 2 Modules 22S2P Module configuration 44 P-groups in series for 163V nominal Dilithium Design BMS with a Thunderstruck 180VDC charger See more projects here: Mac &...

    1 comment

    Electric VW Beetle

    JOSEPH O'CONNOR

    Project in Bellingham, WA Nissan Leaf Gen 2 Modules 22S2P Module configuration 44 P-groups in series for 163V nominal Dilithium Design BMS with a Thunderstruck 180VDC charger See more projects here: Mac &...

    1 comment
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New Additions to the Store

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In Stock Now!

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Learn how to build...

• Second Life EV packs
• DIY Power walls
• High Voltage, High Power batteries
• Mobile, RV and marine backup
• Electric bikes, go-karts
• Electric Cars, EV conversions
• Robots, Drones, and RC vehicles

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Books & Resources

Testimonials for Off Grid Solar Book

"One of the best Solar Energy books of all time!"
- The BookAuthority

"Off Grid Solar is a great starter book for anyone who wants a better understanding of solar energy in general and the potential of "off grid" solar systems specifically."
- Amazon Review

"This is one of the first books on solar that I personally read and it has become required reading for our employees."
-Global Solar Supply

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An image of two battery connector lugs, one vertical and one horizontal, in red color, with a metallic contact end and a plastic body.

DIY Battery Pack

Building your own battery pack? Start here. Products to help you build...

DIY Battery Pack

US Inventory

US Inventory

Battery Cells & Packs

Battery Cells, Modules, or Packs

Battery Cells & Packs

Rebuilding Nissan LEAF Batteries

How to Build a Lithium-Ion Battery System for less than $400 per kWh

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Blog

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  • Cell Review: Sodium-ion NFPP, 18650

    Cell Review: Sodium-ion NFPP, 18650

    JOSEPH O'CONNOR

    Inside Look at Sodium-Ion Cells  Why this matters: Sodium-ion is growing and there are many new variants available, this post talks about specifically NFPP the Sodium-ion cousin to LFP (LiFePo). ...

    Cell Review: Sodium-ion NFPP, 18650

    JOSEPH O'CONNOR

    Inside Look at Sodium-Ion Cells  Why this matters: Sodium-ion is growing and there are many new variants available, this post talks about specifically NFPP the Sodium-ion cousin to LFP (LiFePo). ...

  • Cell Review: Sodium-ion NaCR, 18650

    Cell Review: Sodium-ion NaCR, 18650

    JOSEPH O'CONNOR

    NaCR Sodium-Ion 18650 Cell — Cold-Ready Power Without Lithium Why this matters: These sodium-ion cells are a real alternative to lithium-ion. But which Sodium-ion is the right to choose? These...

    Cell Review: Sodium-ion NaCR, 18650

    JOSEPH O'CONNOR

    NaCR Sodium-Ion 18650 Cell — Cold-Ready Power Without Lithium Why this matters: These sodium-ion cells are a real alternative to lithium-ion. But which Sodium-ion is the right to choose? These...

  • NFPP vs NFM: Which Sodium-Ion Chemistry Is Best for you?

    NFPP vs NFM: Which Sodium-Ion Chemistry Is Best...

    JOSEPH O'CONNOR

    Sodium-ion batteries are quickly emerging as a cost-effective alternative to lithium-ion—especially for stationary energy storage systems. Among the various sodium-ion chemistries, two stand out: NFPP (Sodium Iron Pyrophosphate) NFM (Sodium...

    NFPP vs NFM: Which Sodium-Ion Chemistry Is Best...

    JOSEPH O'CONNOR

    Sodium-ion batteries are quickly emerging as a cost-effective alternative to lithium-ion—especially for stationary energy storage systems. Among the various sodium-ion chemistries, two stand out: NFPP (Sodium Iron Pyrophosphate) NFM (Sodium...

  • Guide to Choosing the Best Battery Management Systems (BMS) for DIY Energy Storage Projects

    Guide to Choosing the Best Battery Management S...

    JOSEPH O'CONNOR

    Battery Management Systems (BMS) are essential components in any DIY energy storage system, offering critical features like cell monitoring, balancing, and protection against overcharge and over-discharge. With so many options...

    Guide to Choosing the Best Battery Management S...

    JOSEPH O'CONNOR

    Battery Management Systems (BMS) are essential components in any DIY energy storage system, offering critical features like cell monitoring, balancing, and protection against overcharge and over-discharge. With so many options...

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