Car Battery Tester 12V 24V 100-2000CCA Lead-Acid Battery, TOPDON BT300P Alternator Tester, Load Tester, with Built-in Printer, Spark Free Metal Clamps, Automatic Reverse Polarity Protection

I had been on the fence about getting a battery analyzer for many years. But since my boat batteries were getting old this year, I decided to buy a tester rather than to find out I had a battery on the water; or have to take my batteries to a shop to be tested. There are a lot of testers out there and it was difficult to make a decision. After reading and watching many reviews, I decided to buy a TOPDON tester. The main factor that made me decide upon the TOPDON was a YouTube video where a guy compared several of these portable electronic analyzers to an expensive shop analyzer from his auto repair shop. In the tests he performed, the TOPDON was closest (if not exactly the same) as the numbers he was getting from an analyzer that costs thousands. Then I had to decide upon model; I didn't want the cheapest one, but I also wanted one with some advanced features. I ended up with the TOPDON BT300P. The BT300P has multiple tests that you can perform on your battery; it also has the advantage of being able to print out the results. I find the print feature to be a nice addition because now I can test my batteries and save the printouts to compare the results of my tests over time. In addition, it will test nearly any type of battery that you desire; you make the battery type and CCA selection when setting up for the test. My thought is that I will be able to see the regression of the batteries over time and be able to make a new purchase decision before I'm left stranded.I tested six batteries with this on the first day I had it: two old Deep Cycle trolling batteries from my boat, one old starting battery from my boat, the main battery from one of my cars; and the two new Deep cycle trolling batteries that I wound up buying for my boat as a result of testing. The boat starting battery came back as good; it definitely is showing its age as the cold cranking amps were a bit lower and the health registered as 83%; but still good nonetheless and it does still work. The two old Deep Cycle batteries were another story. These two batteries were reading good with a multimeter and my boat onboard charger showed green for them as well. But when I tested these two Deep Cycle batteries with the BT300P; it immediately flagged then as having bad cells. So, after that test, I turned on the trolling motor to test them and sure enough it died withing a few minutes of turning it on. If I didn't have this tester, I would have taken my boat out based on multimeter readings and the onboard charger indication; and I would have been stuck out on the water without my trolling motor working. The two new Deep Cycle batteries that I bought tested 100% health and also show more MCA and CCA than the battery was rated at: so definitely good new batteries. My car battery that I tested was really just so I could get a feel for whether or not I would have confidence in this tester. The test on my car battery showed a slight decline in health (91%) and a very small drop in CCA; it was what I would expect from a 3- and 1/2-year-old battery. So, after testing all these batteries, I can honestly say that I do have confidence in the results of this battery tester and given the accuracy, features, and price point I can highly recommend the BT300P if you think you may need to purchase a battery analyzer/tester.Some things to consider that may possible debunk some of the bad reviews here:1. You must know your battery type and CCA and make the proper selection. The first two times that I tested my boat starting battery; it showed failed. I was a bit perplexed as most of the numbers appeared to be adequate. Then, I discovered it was my fault because I was selecting the wrong battery type. Once I verified the battery type and made the right selection; it passed (still providing the same numbers).2. Yes, you do need a good connection to your terminals. This wasn't an issue for me since I keep my terminals clean. But if I were to test my old truck battery; I would probably need to clean things up first. Connection isn't an issue providing that you ensure you have a good clean, corrosion free surface to work with.3. The cables could probably be a bit longer. However, the shorter cable length was not a problem. I would actually rather have the shorter cables as the BT300P does, because longer cables would mean that the tester and cables would require a bigger footprint in my toolbox. The tester and cables fit nicely in the tester tool pouch (included with purchase) and it doesn't take up too much space; like my jumper cables do (for example).CONCLUSION:I am completely satisfied with my purchase of the BT300P. I have been thinking about buying a battery tester for years; but really wasn't sure what to buy. The number of tests available and the results that I experienced in my testing gives me confidence that I can accurately assess the health of my batteries at my home; and gives me the information that I need to make an informed decision of whether to continue using or to replace my batteries. I actually caught the BT300P on a one-day sale, which made it less than the BT200. Had the BT300P not been on sale, I would have bought the BT200. However, the print function of the BT300P is probably worth the extra money since you can keep records of your results to track battery health over the life of the battery. Overall, I am really happy with this purchase and have zero regrets. Just identifying my bad Deep Cycle batteries one time made this purchase pay off and prevented me from having a bad day on the water. It is difficult for me to give the BT300P any rating less than five stars. It's been great so far!

Works great, easy to use. Only issue is the leads could be a little longer for the ripple test

Pretty cool battery tester. It's fast, easy to use, a single press of a printer after reports. It's great and all but the printer can be a issue because it gets stuck underneath and it won't print all the way. It's best to pull the paper out a bit for a opening so it can print out easy. So yeah, best tool ever!

Bought them for my shop so we can test every car. Right of the bat had a few battery tester come apart which felt a bit disappointment but did get a chunk of them. The others kept working for a good year until they eventually gave out as well. Good for not a high volume shop since its not to durable. Aside from that its easy to use and print

Love it and it works great.Very user friendly

As always, topdon knocks it out of the park. I've compared this tester to other well known brands at a much higher price point and every one that one fails, this one fails. Every battery that passes, this passes. 100% worth it. the printer is invaluable for customer trust building.

Tester works great most of the time. Has some flaws like occasional paper jam and says check clamps even tho they're on the battery post. Sadly less than 2 months of ownership and the wiring is separating from the positive clamp. Update i gor contacted by topdon and received a replacement for mine and its been working great for the past month

Fits nice in your hand. The quality and accuracy is the #1 reason I purchased this unit. The battery life is “very long” of course based upon how much use it gets.