XS Power XMAX90-DIY
Contents
XS Power XMAX90-DIY High-Performance 12V Lithium Battery User Manual
Model: XMAX90-DIY | Brand: XS Power
Introduction
This user manual provides essential information for the safe and effective use of your XS Power XMAX90-DIY High-Performance 12V Lithium Battery. Designed for demanding applications such as in-car audio competition, this Lithium Iron Phosphate (LFP) battery offers superior power, durability, and a long lifespan. Please read this manual thoroughly before installation and operation to ensure optimal performance and longevity of your battery.
The XMAX90-DIY is engineered for high-energy accessories, delivering impressive burst wattage and consistent energy with minimal voltage drops. Its sealed, leak-proof, and maintenance-free design, coupled with high shock resistance, ensures reliable operation even in harsh and high-vibration environments.

Figure 1: The XS Power XMAX90-DIY battery with its protective clear top cover removed, showcasing the internal components and robust terminal connections. This view highlights the advanced engineering designed for high-performance applications.
Setup and Installation
Proper setup and installation are crucial for the performance and safety of your XMAX90-DIY battery. Always ensure the vehicle's ignition is off and the negative terminal of the existing battery is disconnected before beginning installation.
Pre-Installation Checks
- Inspect the battery for any signs of damage during shipping.
- Ensure all included hardware (bolts, washers) is present.
- Verify that the installation location is secure, well-ventilated, and free from excessive heat or moisture.
- Confirm compatibility with your vehicle's charging system.

Figure 2: The XS Power XMAX90-DIY battery as packaged, alongside the included terminal bolts and hardware. Ensure all components are present before proceeding with installation.
Installation Steps
- Mounting: Securely mount the battery in an upright position. The compact size (13.82" L x 7.88" H x 7.46" W) and lightweight design (25 lbs) allow for versatile placement.
- Terminal Connections: Connect the positive (+) terminal first, followed by the negative (-) terminal. Use appropriate tools to ensure connections are tight and secure to prevent arcing and ensure optimal power transfer.
- Cable Sizing: Use properly sized cables for your application to handle the battery's high current output (8300 max amps).
- System Integration: If integrating into an existing audio system, ensure all components are correctly wired and fused according to their specifications.

Figure 3: A detailed top-down view of the XS Power XMAX90-DIY battery, highlighting the robust positive and negative terminals. Proper connection to these terminals is essential for safe and efficient power delivery.
Operating Guidelines
The XMAX90-DIY battery is designed for high-performance applications. Adhering to these guidelines will maximize its efficiency and lifespan.
- Charging: Use a charger specifically designed for Lithium Iron Phosphate (LFP) batteries. Avoid using chargers intended for lead-acid batteries, as this can damage the LFP battery.
- Discharge: While the battery is designed for deep cycling, avoid consistently discharging it to extremely low voltage levels. This can reduce overall lifespan.
- Temperature: Operate the battery within its recommended temperature range. Extreme cold or heat can affect performance and longevity.
- Voltage Monitoring: For critical applications, consider installing a voltage monitor to keep track of the battery's state of charge and prevent over-discharge.

Figure 4: A side profile of the XS Power XMAX90-DIY battery, clearly displaying the "xMAX90" model designation and "12V" rating. This view emphasizes the compact and robust construction.
Maintenance
The XMAX90-DIY is a maintenance-free battery, but periodic checks can help ensure its optimal performance and extend its service life.
- Terminal Inspection: Periodically check battery terminals for corrosion or loose connections. Clean terminals with a wire brush if necessary and ensure they are tightly secured.
- Casing Cleanliness: Keep the battery casing clean and free of dirt or debris. A damp cloth can be used for cleaning.
- Storage: If storing the battery for an extended period, ensure it is fully charged and stored in a cool, dry place. Periodic charging (every 3-6 months) is recommended to maintain charge.
- Physical Damage: While designed to be durable and shock-resistant, avoid dropping or subjecting the battery to severe physical impact.

Figure 5: The XS Power XMAX90-DIY battery featuring its transparent top cover, allowing a glimpse of the internal cell arrangement and balancing module. This design ensures protection while allowing for visual inspection of the internal components.
Troubleshooting
If you encounter issues with your XMAX90-DIY battery, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Battery not holding charge | Improper charging, parasitic drain, internal cell imbalance. | Ensure correct LFP charger is used. Check vehicle for parasitic drains. Consult a professional if imbalance is suspected. |
| Low voltage output | Loose connections, undersized cables, excessive load. | Tighten all connections. Verify cable gauge is sufficient for current draw. Reduce load if necessary. |
| Battery not powering devices | Battery discharged, faulty wiring, device malfunction. | Charge the battery. Inspect all wiring for breaks or shorts. Test the device with another power source. |
| Unusual noises or smells | Internal damage, short circuit. | Immediately disconnect the battery. Do not attempt to use. Contact XS Power support. |
If the problem persists after attempting these solutions, please contact XS Power customer support or an authorized dealer for further assistance.
Specifications
Detailed technical specifications for the XS Power XMAX90-DIY 12V Lithium Battery:
- Model: XMAX90-DIY
- Battery Type: Lithium Iron Phosphate (LFP)
- Nominal Voltage: 12V
- Max Amps: 8300A
- Amp-Hours (AH): 90Ah
- Wattage: 20000W (Burst)
- Energy Wh: 1188 Wh
- Ah Pb Eq*: 360 Ah (Lead-Acid Equivalent)
- Item Weight: 25 lbs
- Dimensions (L x H x W): 13.82" x 7.88" x 7.46" (35.1 cm x 20.0 cm x 18.9 cm)
- Design: Sealed, Leak-Proof, Maintenance-Free
- Shock Resistance: High
- Manufacturer Part Number: xMax 90-DIY
- UPC: 810111132510
*Ah Pb Eq: Amp-hours Lead-Acid Equivalent, indicating comparable usable capacity to a lead-acid battery.

Figure 6: Technical drawing illustrating the dimensions of the XS Power XMAX90-DIY battery, including length, height, and width measurements in millimeters for precise installation planning.
Warranty Information
The XS Power XMAX90-DIY battery is backed by a 4-year warranty. This warranty covers defects in materials and workmanship under normal use and service. For warranty claims or detailed terms and conditions, please retain your proof of purchase and contact XS Power customer support or an authorized dealer.
Important: To ensure full coverage and expert support, always purchase XS Power products from an authorized dealer. Products purchased from unauthorized sellers may void your product protection. Each product is tracked by serial number.
Customer Support
For any questions, technical assistance, or support regarding your XS Power XMAX90-DIY battery, please contact XS Power directly or visit their official website. You can also find more information and authorized dealers through the XS Power Store on Amazon.
Always refer to the latest information available from the manufacturer for the most up-to-date support and product details.
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