TOPDON BT100 Car Battery Tester 12V Load Tester, 100-2000 CCA Automotive Alternator Tester Digital Auto Battery Analyzer Charging Cranking System Tester for Car Truck Motorcycle ATV SUV Boat Yacht

Note: This is NOT a carbon pile tester of old but a great tool to perform a quick check. And it is also much lighter, convenient and more compact than Ol Smokey. I found this works best when directly connected to the battery vs the "access nipples" under the hood on my 2024 Audi A5 when testing for load. My battery in is in the trunk under the spare tire. When tested from the access points, the battery tested low but when directly connected, showed up a more believable 55% on the OEM battery. (Note I live in Florida and the heat takes a toll, so I have "learned" to test periodically.) On my bride's Ford Escape, you have to hold your tongue right to get good connections as the battery is under the cowl and I didn't feel like removing the hold downs to pry it out to get a better hands free connection but on that car, it showed a 80% on a 2 yr old Interstate ostensibly made for the hot climate. The other test functions are viable with the most interesting to me the ac ripple test (anyone who owned a 7th gen maxima can appreciate that early warning as those OEM alternators failed regularly every 100,000 to 150,000 miles with High Ripple (don't know if that issue still exists with their diode packs of today but it ran very hot under the hood and those diodes were NOT mil-spec!! :) ) I also appreciated the "dumb guy" indicators when you didn't ensure a good connection. Really helped with those "DOH!" moments. The voltage reading was spot on when compared to my fluke and old Simpson 260b. Nice Job.

I just installed a brand new car battery and checked it with the TOPDON BT100. It showed the battery was bad, which probably saved me from being stranded. The battery was under warranty, so I got a new replacement. The tester is very easy to use and gives clear results. I especially like that it’s a true 3 in 1 tool: it tests battery health, checks the engine crank, and measures the charging system. Now I can conveniently check my battery anytime without going to AutoZone or O’Reilly Auto Parts. This is a great value and definitely worth keeping in the car.

Easy to use and works great. Tested all battery’s, right on the money.

Fast delivery. It's a pretty straightforward piece of equipment. Worked quite well out of the box. Make sure whatever you are connecting to, and the clips, are clean. The reason for only 4-Stars is that like many other testers. The leads are too short to allow a one person operation to do the charging system testing. They need to be at least 2-Meters, 6-Feet long for that test.

Worked as expected and very easy to us even with one person for the rpm part. Would recommend to any home mechanic.

I have been using a 500 amp carbon pile load tester to test lead acid batteries for many years. It works well enough, but it’s large, heavy, and tends to smell bad as it heats up when you use it. It also drains a significant amount of energy from the battery under test to the point where the user manual suggested to charge the battery after running a load, test. Also, the analog voltmeter, is not particularly accurate or easy to read in dim light or at an angle, due to parallax. I bought the TOPDON BT100 with low expectations, but I was proven wrong. The battery health (load) test works by putting a high load on the battery for a very short time, so it does not dissipate much power during the test. This has the advantage of allowing the device to draw very little total energy from the battery and thus generate very little heat. There is also no need to recharge the battery after the test. While the load is applied it measures the battery voltage and calculates the internal resistance of the battery and its capabilities for cranking amps (CA and CCA), as well as displaying its loaded and unloaded voltage. You can set the specified CCA of the battery before the test, which allows it to return a go / no-go result. One of the many advantages of this approach is that the tester is able to determine if the battery clips are not well connected before the test. I tested the BT100 on a number of lead acid batteries, including a 9AH UPS battery, an 18AH UPS battery, a 250AH AGM battery bank that I use for power back up, and my car battery which is rated for 520 CCA. In all cases, I got nearly identical results to the carbon pile tester. In addition to battery health, you can use it while starting the car to measure cranking time and the minimum battery voltage during cranking. You can also use it to test the charging system in your car, and of course, to report the battery idle voltage. Overall, I was pleasantly surprised at the quality results provided by this device. I’ve only owned it for a couple of weeks, so I can’t speak to its longevity, but so far it’s a huge win. Disclaimer: I purchased this with my own money. I was not asked to write this review, and these are my own opinions. Also, I am not an AI bot although I’m not sure how you could tell if I was :)

Works great would recommend for smaller lawn equipment and vehicle batteries

Should be a perfect addition to any tool box for checking home powered equipment. Easy to operate and accurate tool. Price is in the right range for the addition to the tool box.