NERMAK 12V 10Ah Lithium LiFePO4 Deep Cycle Battery, 2000+ Cycles Rechargeable Battery for Solar/Wind Power, Lighting, Power Wheels, Ride-on Toy, Fish Finder and More, Built-in 10A BMS

I picked up this NERMAK 12V 20Ah LiFePO4 Deep Cycle Battery to build out a custom, mobile 12V auxiliary power pack for my outdoor shop tools and high-flow pressure washer supply pumps. To handle outdoor overspray and demanding start-up currents safely, I paired this battery directly with the 12 AWG marine-grade waterproof fuse holders I reviewed previously. This setup has operated flawlessly, proving to be a highly efficient, lightweight power source that works just fine under continuous workshop load. Why this LiFePO4 battery is an exceptional energy upgrade: Shockingly Lightweight Footprint: If you are used to lugging around old-school 12V sealed lead-acid (SLA) batteries, switching to lithium iron phosphate is a total revelation. This 20Ah pack delivers twice the usable energy capacity of a comparable SLA battery at a tiny fraction of the physical weight, making it incredibly easy to integrate into a mobile tool carriage or camping rig. Dependable 20A Built-In BMS Protection: The integrated Battery Management System (BMS) is excellently calibrated. It monitors cell balance and protects against short circuits, over-charging, and deep over-discharging. It handles the continuous high-amperage current draw of my auxiliary water pumps with zero voltage sag, clicking off instantly only during genuine over-current thresholds to protect the internal cells. Flat Voltage Discharge Curve: Unlike lead-acid cells that suffer from constant voltage drops as they deplete, this LiFePO4 battery maintains a rock-solid, steady 12.8V output through nearly 90% of its discharge capacity, keeping connected pumps running at maximum efficiency right until the pack is empty. Workshop Wiring & Charging Tips: Always Pair with Circuit Safety: Because lithium batteries can discharge energy incredibly fast during a dead short, do not wire them raw. Follow my previous build steps and splice a dedicated in-line fuse holder (equipped with a 20A fuse to match the BMS ceiling) directly onto the positive lead wire right at the terminal. Utilize a Dedicated LiFePO4 Charger: Do not attempt to charge this with a legacy automotive lead-acid battery tender. Lithium chemistry requires a specific multi-stage charging algorithm (typically pushing a bulk charge up to 14.4V–14.6V) to properly balance the internal cells and hit that advertised 2000+ cycle lifespan. The big takeaway: NERMAK has delivered a premier, ruggedly housed power cell that offers an unbeatable combination of capacity density and safety features for a very reasonable price. The screw-down terminal posts are clean and provide a rock-solid mechanical connection point, the internal protection circuits are highly responsive, and the weight savings are massive. It is an exceptional value purchase that modernizes any custom low-voltage electrical build.

I needed replacement battery for my Tzora electric scooter, and the 25 AH lead acid battery pack. This barely fit into the enclosure of the lead acid battery, I had to modify it somewhat, so I could not recommend it for that use. In other scooters, it should fit great. If you are handy with tools, then it might work great for you as well. It seems to offer a higher voltage than the 25 AH lead acid battery, the voltage always reads top of the range in the volt meter. It does not sag as much when going up a incline. It feels more powerful than the 25 AH battery it replaced. But it also has the problem of shutting off when the voltage is low, not just slowing to a crawl when the voltage is low like a lead acid battery. It is a safety feature of all lithium battery packs to shut themselves off at a low voltage cut out. Just be sure to recharge it more often. I would expect a longer range than the 25 AH lead acid battery, and many more recharges than lead acid style battery.

So far so good. This is the second battery I buy from this vendor, and after observing good performance over a year or so, I felt compelled to write a review. The first battery was used for a kids ride on jeep running at 12V. This second battery was to upgrade that same ride on toy to 24V by connecting to the older battery in series. It seems the overcharge, overvoltage, and fault protection in the BMS circuit actually works. We have done all of the above and it still works. I didn't do a formal leakage test, but I know for a fact that it holds charge well over decently long periods of time and cold weather. As long as they don't change their process and material, it's totally good value for your money.

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.

Just ordered this for my daughters offbrand Power Wheels Jeep and man, this thing is so light and holds a charge for a lot longer than her other 12v battery. (16Ah is to thank for that I’m sure). I haven’t tested it to see how long exactly it works, but we made it to the store and grandmas and back the long way which was our destinations so that’s all I needed. Thanks!

Purchased six batteries to replace SLA batteries in 4 UPS, one CP 1500, CP 1350, APC ES550, and AT&T Gateway UPS. All had previously used 7Ah sized batteries, with the CP 1500 using 9Ah. This battery brand is taller than common SLA size. It required me to #D print a thinner spacer out of PETG for the twin battery CP 1500 and CP 1350 UPS's. All work with caveats, the CP 1500 draws no problem (2.5hrs, 4% load), but cannot charge the batteries when fully depleted, tripped BMS. I added an external Lifepo4 charger to the terminals and plugged it into the non-ups plug on the UPS, so it chargers when the utility is energized. Solved that issue. Sits at 14.9v. The CP 1350 does not like a light load (30w router and gateway) and trips the BMS in a few minutes when I pull the plug. It goes against reason. I'm going to swap these batteries to another battery brand eventually, or add a higher draw to see if that corrects the issue. The APC ES550 sits at 13.6v and runs quite well on battery with a 2% load for over 1 hour disconnected from utility.. The AT&T (Belkin) Gateway backup has survived several power outages for 30+ mins and is charging well. No stats on that unit. 2 single battery UPS work, 1 twin battery UPS (24v) with an external charger work, and 1 twin battery UPS (24v) not so much with external charger. I added a PwrMr 24v charge balancer to both CP 1500 and CP 1350, but those did not make any difference and I removed them. My research and observation is that these batteries work better in APC units, and are finicky in Cyber Power units. If you already have a SLA UPS, it's worth a shot and a hell of a lot cheaper, but I don't recommend these batteries with Cyber Power twin battery SLA (24v) UPS. If you dont have a SLA UPS, either get one for $10, or just buy a dedicated Lifepo4 UPS and save time and trouble. Battery condition, discharge, charge, and capacity seem good with these.

Very pleased. I used these batts to replace heavy lead batteries for my GoPed 750 ESR. It's almost the OG of electric scooters and have given mine, a new life. I know can travel further and faster with the new batts and they are crazy light weight. I can lift my scoot on the train with ease. I rarely give five stars but this is one purchase that really made a difference.

Update 4 days later, 10/11/2024 Well...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 10/7/2024 Very 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.

después de meses usándolas, diversos cortes de energía al en estos meses, puedo decir que respaldan mucho mejor que las que traía mi UPS de ácido, sin duda compraré más este tipo de productos por su relación precio/calidad