12V 18Ah Lithium LiFePO4 Deep Cycle Battery, 2000+ Cycles Lithium Iron Phosphate Rechargeable Battery for Solar Power, UPS, Lighting, Marine, Scooters, Fish Finder and More, Built-in 20A BMS

Due to frequent pwr outage in S.Cal I was looking for replacement batteries for two UPS units. These APC-brand units are over 10 yrs old but are working like champs. The lead acid batteries have been replaced twice and each last roughly 4-5yrs. Initially I was not sure about the charging compatibility b/w Lead Acid and LiFePO, but after reading other ppl's reviews and internet posts, I ordered two battries and surely enough these two units were put to work and test in realtime. Happy to see at one long outage they lasted twice longer (from 3 hrs to 6 hrs) on a relatively low load of 110-130Watts. The battery is fully charged within 1hrs when power is back. It costed a little more than lead one but for the extra $ it's worth. Beside it's half the weight of lead acid ones, when you get older you will appreciate the weight difference. I used LiFePO in RC-controlled airplanes so I love these powerful but lighter one. Seller is very responsive to my concern and timely addressed my inquiry. Highly recommended.

These are well made Lithium Iron Phosphate batteries that are spot on for the voltage and are a great value due to the built in charge controller. They are easy to install as they perfectly match the size of the lead acid batteries they are replacing. After doing a UPS test we found that are a great battery replacement and deliver even more power than the older lead acid batteries did.

Update 4 days later, 10/11/2024Well...this did not work out.The battery arrived and was installed on Monday, just before Hurricane Milton struck Wednesday night. After a1/2 second test crank (which was fine), the battery was connected to a new LiFePo4 battery charger designed for this battery chemistry. The charger itself may be suspect, as the battery would not accept a charge. The charger displayed a fault mode after a few hours. I then connected it to a known good charger. After a charge of several hours at 2amps, the charger had to be disconnected as we prepped for the storm.A quick check on Tuesday (the next day) found that the generator would not start. Did not have time to do diagnostics with the storm coming. Had to pull-start the generator after we lost power Wednesday evening.Did diagnostics today, Friday 10/11. No problem with the starter motor, as it started immediately with my portable jumper pack. The Nermark battery showed less than 10V on my DVM. Both chargers displayed a battery fault, and were unable to charge the battery above 10.3V. It's possible there was an issue with the built-in BMS (Battery Management System), but I don't know. It's getting returned once Whole Foods is open again.Original Review 10/7/2024Very simple installation to remove the old sealed lead acid 12-18 battery and replace it with this one. I have been using LiFePo4 batteries in my RC aircraft for over 20 years and I'm glad that this battery is available to replace the typical unreliable lead acid battery that is used as a starter in portable equipment. I took the opportunity to install the terminal rings and cable for the appropriate 3 amp charger and even without completing the charge, did a quick test start on my generator.I hope it will last several years, as this generator is only used for hurricane emergencies. However, I have batteries of this chemistry that are over 20 years old and still hold 80% or more of their charge.I will report back and update this review in the event that there are any failures, or possibly great news to continue to report years from now.

I’d recommend against usage for “legacy” UPS lead acid battery replacement, specifically the common case of quantity 4 or 2 battery systems. These usually are setup with the batteries in series (4x12v = 48v, 2x12v=24v).You are likely better off throwing the legacy lead acid battery UPS away, and buying a lifepo4 based UPS. Even the Lifepo4 portable batteries like the power 1000 have UPS capability. The ups devices that start with a lifepo4 energy source usually have passive and active cooling for the battery array, in addition to the inverter components.There are a few problems with using these in a legacy lead acid battery UPS:1. The continuous output current is far lower than lead acid batteries. The typical Lifepo4 compatible battery option is rated at 10amp continuous. So, in a 4 battery series system, you’ll get at most about 135w continuous output per battery - so about 500watt max. You won’t get anything near the potential needed in common 1000w, 1500w, and 2000w ups.2. The BMS present in the lifepo4 batteries generally needs at least exposed passive cooling, or even active cooling. These are enclosed package batteries, so cooling is limited at best.3. With 4 12v lifepo4 batteries in series, you’d basically need another BMS to manage the 4 batteries, or the discharge and charge levels between batteries becomes imbalanced.4. The charging circuit will not fully charge lifepo4 batteries, in most cases. Lead acid vs. lifepo4 have different max voltage levels.5. The legacy ups doesn’t know the proper estimated runtime or charge level of lifepo4 batteries. This is a relatively minor issue compared to above.Technically, a 48v lifepo4 pack that fits most UPS battery compartments could be built to handle several of the issues above.As an experiment, I fully charged up 4 of these individually outside a UPS, then installed them in the ups. Verified the output of the pack was approx 55.8v. The charge/discharge circuit ”popped” with the telltale electronics burning smell, with smoke, when a 200w load AC power fail test was triggered.These batteries may be ok for some cases, like the single battery backup common to home alarm system panels.

This battery has a much higher amp hour rating than traditional lead acid. It has the same dimensions and discharge voltage, it's all around the best choice for losing weight and increasing reliability. Provides almost 2 hours of run time vs. Less than an hour on a new lead acid battery.