DR.PREPARE 12V 20Ah LiFePO4 Lithium Battery with Grade A+ Cells, 4000+ Deep Cycle Lithium Iron Phosphate Rechargeable Battery with 20A BMS for Fish Finder, Solar, Lighting, Alarm System

After a full initial charge, I discharged the battery down to 10.5 V, and it rebounded quickly to 11 V. So far, I’m very happy with the performance. This test was done at a 2-amp discharge rate, and the voltage stayed extremely steady right up until cutoff. A heavier load test is coming next. Before running a higher-current test on the 20 Ah battery, I also tested the 100 Ah battery I purchased—and the results were excellent. I had to be gentle with my tester to pull enough current over a reasonable time span, but I managed to measure 99.12 Ah over approximately 9 hours and 57 minutes, at an estimated 8–10 amp draw. These were the very first charge and discharge tests, completed within days of receiving the batteries. I plan to continue testing and will update this review if anything changes. As of now, $120 for 100 Ah and $46 for 20 Ah feels like a very solid value. Update (2-7-26): After a few months of light, occasional use, both batteries are still performing great. I recently purchased a BT90 Pro battery tester with lithium testing capability. After partially discharging the 100 Ah battery and letting it sit unused for a couple of months, the tester still reported it as being in excellent, full-charge condition. Out of curiosity, I also tested the battery’s 100-amp maximum discharge rating using a Harbor Freight CEN-TECH 100-amp load tester. It successfully delivered 100 amps for 9 seconds without the voltage dropping below 12.6 V. The battery stayed cool throughout the test, and the BMS did not trip. Everything continues to work exactly as expected. I’ll keep testing and updating if anything changes.

Bigger and heavier than I expected but works

this battery died and never was able to charge again. I contact the seller, or they contacted me to replace it, however, they gave me a bs answer and was like we sending you a box what is your address. I said it is the same address you all sent to so they were kind but horrible customer service. It worked that one time for a long time. I had it in a battery box so it would not get wet, and it did not, but the dam thing died. So does not work well, does not charge straight trash and I am still waiting for a replacement or the box to send it back as they lie it should of been here months ago.

I purchased two of these for use in a portable battery box and was pleasantly surprised by their size. Their relatively narrow width allowed me to fit both side by side in a plastic .50 caliber ammo can with room to spare for wiring. It hasn't seen much use yet so I can't speak for battery life but, if I need batteries for a similar project, these will be a go-to.

Great batteries. Got them for my brother who has leg problems for his mobility scooter and hot damn, the scooter goes faster than ever. I just got them so I will write another review in 6 months .

Bought to replace generator battery. I wanted something that has more capacity and cranking power. Works well.

Battery won’t hold a charge and only 2 months old

This battery works really well, I use it on my fish finder and it works great.