My 2004 Prius was recently totaled in an accident that was caused by someone making a blind lane change, but my father has a 2005 Prius that he isn't using for, reasons, with dead hybrid and auxiliary batteries. The auxiliary is easy enough to replace, but what's the best replacement for the hybrid battery? I've never been in a position to do a full replacement. I've read about refurbished NiMH batteries, new builds, lithium ion, and sodium ion, and I have no idea where to go from here. Which type, company, etc.? Any advice would be appreciated.
If you want to keep using battery chemistry that was considered the most advanced/modern in late 80's early 90's then stick with OEM. But if you want a future proof solution that will be the most advanced/modern battery chemistry of the late 20's and early 30's you want a Sodium-Ion pack which will improve your Prius overall performance in many, mnay ways. Just head to www.saltyhybrid.com and scroll down and find an installer near you who can order a pack and install it for you.
If you want to keep using the same battery chemistry that Toyota designed the car for, use NiNH. If you want to use a battery chemistry that the car was not designed for, use sodium-ion. Be advised that the company (Nexpower Energy) that supplies the sodium-ion battery is the same company that sold Nexcell LiFePo4 batteries which had many warranty claims and almost bankrupted the company. Nexpower did not fully honor their warranty for the LiFePo4 batteries. They only offered a partial warranty towards the purchase of a replacement sodium-ion battery. Nexpower is changing their business model from selling directly to consumers to selling wholesale to battery installation companies like Hybridgeek. So, the sodium-ion battery that you see listed on the Hybridgeek website for $2,795 installed, utilizes the Nexpower sodium-ion modules. Be advised that PriusCamper also aggressively promoted the Nexpower Nexcell LiFePo4 batteries and collected a referral fee. He no longer gets any referral fees for promoting the sodium-ion battery. You can do a search on PriusChat and learn yourself about the proplems with the LiFePo4 battery or you can visit the FAQ page on the Nexpower website.
@Brian1954, yes, I’ll admit it — the lithium LiFePO4 chemistry was not the right solution for every condition. Some customers had repeated issues, and the warranty replacements nearly bankrupted the company. In late 2023, I had a choice: declare bankruptcy and walk away, or take responsibility and fight for a better solution. I chose to stay. I took a loan against my house, spent my last dollar on R&D, and started over. That work led us to sodium-ion. It was not easy. All my friends know that the stress and debt had broke me, I was hospitalized for months. But I survived, and I didn’t quit. Fast forward to 2026: sodium-ion has reshaped the entire hybrid industry, helped us repay the debt, some companies exclusively using only Sodium-ion battery. We start hiring, and begin bringing manufacturing back to the United States. We are now investing in CNC machines, laser welders, laser cutters, lathe and automation equipment to build battery right here in the US. Brian, you may not care, but I still want to thank you for your criticism throughout the years. It only made me stronger, without you we probably won't even exist in 2026! Best regards, Jack
Sodium Ion is the way to go. Great price, it's light, easy to install. Holds up in both heat and cold. You're mpg will improve, more power. Not a Huge amount of course, it is a Prius. But you will notice the improvement. You're also be able to run in ev mode a lot longer. Charges quicker, and holds the charger longer. You certainly do NOT want a rebuilt or refurbished battery. They don't last. Everyone has issues with them.
