ANCEL BM200-US Car Battery Tester 12V Automotive Battery Monitor Bluetooth Auto Battery Load Tester with Cranking Charging Test Alarm Record Voltage History Voltmeter for Car/RV/Motorcycle/Truck/Boat

This has been great for monitoring the battery on my electric lawn mower, the readings are accurate and easy to read, good quality and it has held up great in the past year since install. I love the app and other tech features and the price was not bad for all that you get. Easy to use if you read the instructions or watch the video on youtube. Features on the app are also worth a look.

I don't drive my truck a lot lately and as a result battery has gone dead a few times. I got this so I can check the battery remotely and it will also send a notification if your battery falls to a certain level that you can adjust in the app settings. It works perfectly from behind the wheel, I'm able to park almost directly under my bedroom window it should work fine from there too if I open the window. Bluetooth is a short range technology, most folks are saying under fifteen feet which is fine with me. There are a few tenders available that have wifi capabilities but this gadget is more versatile because you can use it with any charger or a solar panel etc. and keep an eye on your battery level remotely. The unit also has other functions that I have no plans to use at the moment but adds to the value of the item for sure. I had zero problems finding the app with the convenient scan box on the box the item comes in and the app had zero issues finding the gadget and pairing with it (make sure bluetooth is on before you install the software, the gadget comes on in pair mode like many if not most bluetooth gadgets these days. So far so good, it would appear they've improved things or I just lucked out and don't have any interference at my house. Does what I wanted, lets me monitor car battery voltage without getting into the engine compartment. You will automatically get a notification every day from the unit but it will only show current battery voltage level which is what I wanted it for. update roughly three weeks later: Item still working great but this morning when I started up the app it could not see the battery in my car only a couple feet away. I have noticed that sometimes with products using bluetooth an app update might mean you have to restart the phone/tablet or rarely even reinstall the bluetooth gadget before things start working correctly again. I don't know if there was an app update, it was in the 20's outside this morning but that shouldn't have been cold enough to create a problem. Turned the phone off and restarted, all working again so be aware that if you have issues you possibly need to turn off your phone and restart to get it working again (not a biggie). I put my new nocco genius 10 charger on the battery (probably stay away from where you have the gadget connectors on the battery just in case) and used the app to monitor the charging works perfectly shows voltage coming off the battery and percentage charged to get any more info you have to start the car up. It's now almost April of 2025 been using this about six months. Item still working perfectly and I can sit in my bedroom and pickup the bluetooth connection off the truck parked outside my window. It's doing what I wanted it for, making sure my battery doesn't go dead because I don't drive the truck enough. I'd recommend this little add on to anyone with a vehicle they don't drive every day but need it to start when you need to drive it. September 2025 bought a solar charger (schumacher) because my one outdoor outlet on that side of the house developed an issue. This item lets me monitor the battery even running off a solar panel charger. This was such a good purchase and it didn't cost that much at all. Would definitely get this item again if I change vehicles.

Update 1/27/25 to my original review. I received a replacement unit that now works for downloading the data locally. As far as calculating the fuel usage by MPG, when in Imperial units, Not metric units, I simply put the cost of a gallon of gas and MPG for the other field. I ignored the liters note in the little message area. I also confirmed that the unit had the latest firmware installed. So overall, I am very impressed with the performance and by the way, customer support was excellent also. --- First Review: Some features in this I liked, and some I did not like. First off, it was easy to hookup and get the Bluetooth working. However I could not get the data to download no matter what I did. I wanted to be able to download the data to compare historical data from time to time on a battery setup. And so maybe I had a unit that simply did not work for downloading. One feature that I did like was the fact that I could fine tune the battery discharge curve based on custom type. But for the most part it had both LiFePo4 and Lead Acid batteries you could select from the menu. Another feature that didn't make sense is they have it so you can put it into American settings, but not everything. For example, they have the option to put in data for 100 kilometers of driving, though there wasn't a way to enter miles. That was strange that they didn't have that conversion built in. The Bluetooth portion works well, and is really designed for close use only. I wanted to be able to monitor the voltage while driving at times, and that was the cool part. I really didn't expect it to go long distances, because Bluetooth is not designed for long distances. I'm not sure how the Bluetooth part works for finding your car, I didn't really give that a chance to see how it works. So this Ancel unit definitely has its pros and cons, and the pros outweigh the cons, but in the end I returned it because I could not get the data exported. Like I mentioned, maybe I had a bad unit.

I’ve been using the ANCEL BM200-US for a few weeks now, and overall, it does the job well. It’s easy to set up, connects via Bluetooth without issues, and gives a clear readout of cranking and charging tests. I like having voltage history —super helpful for keeping tabs on my battery’s health. That said, the data export feature is a bit clunky. It’s not very user-friendly if you want to dig into the numbers outside the app. Also, the State of Charge (SoC) calculation seems off, even though I double-checked that I selected the correct battery type. Not a dealbreaker, but definitely something to be aware of. Still, for the price and the features it offers, it’s a solid tool to have on hand for car, RV, or motorcycle maintenance.

I found the Ancel BM200 to be accurate and simple to use The display size was east to read and it a great way to test your batteries and feel comfortable knowing at all times. I also like the functionality of the app. I give it a 10/10 and I've already ordered 5 more to go on all of my boat batteries. They also have built-in GPS so you can track your car at all times its just an awesome product. Worth it!

This thing is driving me crazy I bought a brand new AGM group 65 battery and I ordered this to keep an eye on it and it keeps showing me lower voltage compared to the voltage display I have in the car and my OBDII reader. This device shows me battery SOC(Stare of Charge) goes from showing 12.8v and 100% SOC right after shutting the car off to 54% to 58% and 12.0 to 12.2v after I leave the car for about 5 to 6 hours I almost went and returned the battery because I thought it didn't hold charge but I also have a voltage display on my phone charger in the car and that one shows 12.6 to 12.8 even after 5 to 6 hours so I decided to hook up my obdII reader without starting the engine just the key turned to ACC and the obdII reader showed me 12.6 to 12.8 volts after 5 to 6 hours also same as the display on my car phone charger inside the car. Even when the bm200 shows 12.0 volts and 55% SOC when I start the car and look at the cranking test the car cranks really good the voltage only drops to 10.7 to 10.9 volts each time which is a sign of a very healthy battery so there is no way my batteries SOC is at 55% because at that percentage the car would crank slower and the cranking voltage would definitely drop below 9.6 volts at 55% SOC. I have the BM200 set to AGM battery so it can't be that I have it set at a wrong battery type I even went and replaced my battery terminals to really expensive thick copper ones because I thought maybe they were worn out and they really did need changing but nothing changed on the BM200 it still keeps displaying lower voltage than all other devices and yes the BM200 is hooked up to my battery terminals. While the engine is running it's same thing my phone charger and OBDII reader shows charging at 14.6 to 14.7 volts and the BM200 shows 14.0 to 14.2. It's completely driving me crazy because I keep thinking the brand new AGM battery is faulty but than my other 2 devices and cranking test show it's a perfectly healthy battery working like it should.

Updated review: I ripped this product apart and I was not nice to customer support. They stayed professional and both offered a refund and help with the issue. I ended up taking the advice, and customizing the settings. They have gained a customer for life based on actual customer care, even a bad customer. The product now works perfectly now that it is configuered properly. Im leaving my original review after this. My new review is 10 stars. Old review: Even when my new lithium 300AH battery is at 100%, this device only reads 82%. My battery had its own display, but hard to get to where i hands it installed. I had hoped this would work in my camper van, but turned out less than ideal. No load on it, full battery, still says 82 max

I hope this will help so here is some information: The good: This is a nice unit and the app is easy to use and shows history of the battery voltage which is nice. The voltage readings are very accurate I tested against one of my voltmeters and it was spot on. It has customizable voltage warning setting if the battery gets to or below a certain voltage percentage. It has a vehicle charging and starting battery test which is nice. Overall accurate and nice app to keep an eye on your batteries voltage. It also shows the temperature which when compared to my other known good temperature guns was within 2 degrees so decent accuracy on temp. The Bad: Bluetooth range is only like 20 feet max. The app doesn't run in the background so you won't get a low battery or high voltage alert unless you leave the app open. You can't fully customize the battery type but it does have standard or lithium but you have no control over the voltage vs state of charge. It just uses a generic automotive12v type battery voltage for its reference. So if you have a 15v lithium or something it will say fully charged even if its 70% charged. But this was designed for automotive type batteries so i guess its just doing what it was meant to do.