NERMAK 12V 50Ah Lithium Iron Phosphate Deep Cycle Battery

Alejandro FernandezAlejandro Fernandez: Excellent replacement battery for my Stanley Fat Max 700. Fat Max is much lighter too. The air compressor works much better. Works very well for booster jumps too. 1 year update…Nov, 2023. My OEM 12V Stanley charge system failed. Charge bars, USB, light, Air compressor and jumper still work great. I now turn the booster cables to “ON” and use a $25 12V 10A trickle charger to fully charge Stanley in 2 hours. This battery has been holding up great.

United States on Nov 05, 2023

Brandon Tarbet: I just installed this in a CP1000 AVR by Cyber Power. I've had the unit for 9 years with the original battery and installed another brand of AGM (8 amp hr) and tested the unit. It gave my PC and network equipment about 18 minutes of runtime.
This 10 AMP Hr LiFePh battery gave 21 before I plugged it back in and the Cyber power UPS said it had another 2 minutes of potential runtime. So, though I did not do an actual draw down load test and recharge, it seems appropriately rated. The price for a LiFePh battery was excellent (in my opinion). .
I can't speak to longevity yet, but if the battery management system in the unit is any good, then it should last a long time, as LiFePh chemistry is generally more robust than AGM or lead acid style batteries.

United States on Oct 25, 2023

Bruce E. Day: Now LiFePO4 price has come down and lead acid has gone up, it makes sense to try a supposedly more durable battery. I was concerned about compatibility with the current APC unit using a 7AH lead acid. This one is a perfect fit and after a couple of months is working fine. It will be 5 years before true longevity will show. 2023-10-24 update. Turns out the LiFePO4 battery does not function well in the APC Back ups. The form factor and software would indicate it's a drop in replacement. However, when the line current is removed, my desktop computer loses power and does an uncontrolled immediate shutdown. This does not happen with a sealed lead acid battery. Less power demanding devices such as the LED monitor and network switch stay on. I'm no electrical engineer so can't say why this happens, can only report it.

United States on Oct 08, 2023

Ron Cartwright: I purchased these batteries because they are 50 amp hour, I use 8 eight at a time for my application, the first use was great and the batteries lasted 70 cycles with the factory charge, after that I was getting inconsistent cycle use, the batteries would not charge full. I have two 4 types of 4 bank chargers, one charges the batteries better then the other. I contacted Nermak, their customer service teem was very responsive, several emails back and forth, we are going to try another battery charger that they recommend. I will not be using these batteries until Jan 2024, I will f/u with a review after that. Very pleased with the customer service department.

United States on Oct 06, 2023

R.Hector CamposR.Hector Campos: I ordered this battery to replace the lead cell battery in the Stanley Fatmax 450A starter unit. The battery is accessed by removing about 8-10 Phillips screws on the bottom of the unit. Disconnect the battery and replace with the Nermak 12V 20ah battery. Pretty good fit. I did go up in amperage to provide a little more power and hopefully usefulness for the unit. I did have to reroute the negative cable slightly to get the battery in. Goodness what a difference in weight. The battery was partially charged upon arrival and ran the light and air compressor right away. I don't know yet about reliability and longevity but if it's anything like the battery I installed on my solar power gate operator a year ago. It should be trouble free. UPDATE: On 09/14/2023- As it turns out on the following morning my wife's car wouldn't start. I used the FatMax and it jump started up the car on the first turn! One thing I didn't mention on the install. The original battery had lug posts for the positive and negative connections. This battery has surface mounted connections with included bolts. I just used pliers to straighten the lug wire terminals and bolted each set of wires to the corresponding...

United States on Sep 13, 2023