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Availability:
In Stock.
Arrives
Aug 8 – Aug 10
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Description
Ioxus UltraCapacitor is a Smart Power ultracapacitor-based product for vehicles that improves starting reliability, improves vehicle voltage health, improves battery life, and improves sustainability. With a 15-year design life, you will never change your ultracapacitor again.
Capacitance: 375 Farad
Brand: Generic
Material: Aluminum
Shape: Round
Operating Voltage: 12 Volts
Product Dimensions : 13 x 13 x 9.45 inches; 38.51 Pounds
Item model number : UC-31
Date First Available : November 3, 2022
Manufacturer : IOXUS
Best Sellers Rank: #67,660 in Automotive (See Top 100 in Automotive) #181 in Power Inverters
#181 in Power Inverters:
Customer Reviews: 4.2 4.2 out of 5 stars 173 ratings
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Aug 8 – Aug 10
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To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Top Amazon Reviews
I have to give this 5 stars!!! I was on the highway and my alternator light started flashing. I knew I had the proper wiring (1/0 ofc wiring) for the AGM and the ultra cap ran properly. This thing is a real beast, I was able to make it 135 miles with a dying alternator in a full size conversion van. I’ve had a 5000w audio system and a 200 amp alternator no dimming very easy to monitor with the voltage app and the price was incredible. I highly recommend this for your van life build or as an addition to your car audio system.
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Reviewed in the United States on June 18, 2025 by Ray Kustoms
These things are used but for the price you can pick one up for now is a bargain. A lot of capacitors out there you can spend $70-$120 and get only 10 fareds. That won’t help much. This thing has 375 fared. Before installing this my voltage would drop to 13 volts sometimes. From 13 volts to 14.5 volts for amplifiers is huge for the output. I actually had to adjust the gain on my amps and the overall sound quality is noticeably better. I have about 700-800 watts and it does ok for that. If you have 1000 + watts I would recommend two or a capacitor bank with about 1000 fareds.
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Reviewed in the United States on June 13, 2025 by Ozzy’s Tamales
Definitely makes you music more punch helpful with the voltage I am seeing 200 W more on my meter package was great quality
Reviewed in the United States on June 7, 2025 by Amanda s.
These are great especially at this price, with a BIG caveat - they shouldn't be used in vehicles due to a recall/risk of FIRE. I have purchased two of these to use for an art project, and a portable 12v sound system. The art project used cheap 3000w class D amps paired with dual 100A 12v power supplies and this capacitor to drive 3000w of haptic transducers without voltage drop. The sound system is 1200w RMS of subwoofers + 700w RMS of tops using LiFePO4 batteries + this capacitor for portable / generator free PA system. They have been great for these applications. The reason these are cheap though is because they were recalled for potential fire risk - that's why "B Stock" that people receive are used items. They shouldn't be used as a starter / car audio install for this reason. -------- This capacitor module was previously the subject of two NHTSA motor vehicle safety recalls for use in on-road vehicles due to the possibility of an internal short resulting in energy from the battery draining into the power board, further resulting in smoke and possibly fire. For further information, refer to NHTSA Recall Notice Nos. 19E078 and 19V916, available at nhtsa.gov/recalls. Resale of the capacitor module for on-road use is illegal under federal law. The risk of an internal short leading to a thermal event remains in using the capacitor module in an off-road application. Purchaser hereby releases and agrees to indemnify and hold Systematic Power Solutions, LLC, SVJ Holdings, LLC and Systematic Power Manufacturing, LLC harmless from and against any and all claims, damages and judgments arising from use of this capacitor module in any application whatsoever, resulting in damage to person (including death) or property.
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Reviewed in the United States on April 8, 2025 by Tahoe Local
Put out less than 15% of the indicated capacity. Would not hold a charge, seemed to have an internal short, likely in the control board. It is possible that the issue with capacitance/energy storage was just a single unit failure. I did not order/request a replacement, therefore had only the single unit to evaluate.
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Reviewed in the United States on July 14, 2025 by Oscar
Workes great!! Can definitely feel the extra ummph in my sound system!! Would buy 2 since I'm only at 3000 watts now and plan to go 8k this year! Only problem I've seen is that it will not shut off if you connected next to your back battery bank without an isolator.. I have a couple extra isolators so now a problem for me
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Reviewed in the United States on May 10, 2025 by Erin
Realistically for the price, you're not going to beat it. I use this on my system to help reduce voltage drop and I push around 3000 Watts. I recently swapped over my entire system to my new (to me) daily. The battery was so low it wouldn't start because I had the doors open all day trying to hook up my system and I turned on the app and put it in run mode and it fired right up. Definitely help keep my last car running because it went through alternators because of sound systems without capacitors before I got this thing. And it already has a lot of bad grounds but it stayed running because of this thing. I'll probably get a second one and some kind of solar charging mechanism to go with alternator charging just to be safe when I upgrade my amp to something bigger.
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Reviewed in the United States on March 3, 2025 by C Hawley C Hawley
Pretty beat up, I was worried that it wasn’t going to work but it works great. Good price I see other places post this thing for a crazy amount ($600Usd) but it’s probably new. Chop down $460 for a used that works great and would absolutely recommend if you’re on a budget.
Reviewed in the United States on April 8, 2025 by Koby Atencio