Frequently Asked Questions (FAQ)

Welcome to the SunmaxSolary FAQ page.
Here you'll find quick answers to the most common questions about our products, shipping, warranties, and technical support.

If your question isn’t listed here, feel free to 👉 contact us → — we’re always happy to help!

1. What is the difference between SOK Batteries and RUiXU batteries?

SOK batteries are drop-in LiFePO4 units, ideal for RVs and portable setups.
RUiXU batteries are rack-mounted systems built for solar homes and hybrid inverters.

2. Can I use your batteries with my existing inverter?

Yes—our batteries support most inverters. See our inverters for more details.

3. Do I need a BMS?

All our batteries come with a built-in smart BMS, no separate purchase required.

👉 Read about BMS Protection →

4. What is the warranty period?

SOK: 7 years  [Download SOK Warranty PDF]
RUiXU: 10 years [Download RUiXU Warranty PDF]
See full terms on our 👉Warranty & Return Policy.

5. Are your batteries safe to use in cold weather?

Yes. Many models include low-temp charging protection and self-heating.
See 👉Smart Battery Features for more info.

6. How long do your batteries last?

Most LiFePO₄ units last 4000–8000 cycles. That’s 10+ years with proper use.
Read more on 👉Cycle Life & DoD.

7. Where do you ship from?

All products ship from our U.S.-based warehouse. (Ship From Address: 3969 E Guasti Rd Ste C, Ontario, CA 91761, USA)
Delivery typically takes 3–14 business days.

9. Do you ship outside the U.S.?

We ship to all 48 contiguous U.S. states. For Alaska, Hawaii, or international orders, contact us for a quote.

10. Can I return a battery if I change my mind?

Unused items may be returned within 30 days. Used batteries can only be returned if defective.
Details on 👉Warranty & Return Policy