BM2 Bluetooth Battery Monitor 6V-20V. 12V Battery Tester for Car, Campervan, Motorcycle, Boat & Leisure Battery. Wireless Monitor App for iOS & Android

Have had this running for a few days now on my motorhome leisure battery. Works exactly as described and automatically connects to the app when in range. Device collects and saves battery information. Really easy to install. Provides peace of mind particularly when off grid. Tested accuracy against a meter and very accurate. Use it as a guide and an early warning of battery drain, battery level/fault or charging/fault. Would recommend.

Wasn't too sure about these as so many out there but I'm running ecoworth batteries in my converted van and although I have inverter and solar I wanted a direct battery monitor. Yes its Bluetooth so no display screen but what can I say... I have wifi and a tablet that shows my vans smart system. I was able to connect this to my tablet and display the statistics. It can also be accessed by phone as well. The readings were correct as cross confirmed with my solar. Very easy to install, plug play and load up the app and it will automatically detect. Very good value for money as less than half the price of those provided by Victon

I purchased this battery monitor to use with my 12v solar setup. I charge a 12v AGM battery which we use to power our bedroom TV. I wanted a battery monitor that i could check on my phone to see how much charge i had left within the battery. The device is small and compact and is fitted easily to the battery terminals. You also get a piece of velcro to attach to the battery. Once installed you download a free app called Battery Monitor. The app will then ask what type of battery you have the monitor connected too, i selected AGM. You are then provided with the voltage and estimated SOC, along with a pretty nice graph which shows the discharge/charge rate. The app also allows you to look back over time at the various voltages of the battery. I found the functions very useful. My only issue with this battery monitor is the accuracy of the SOC, i think the voltage is pretty accurate but the SOC seems wildly off. Comparing the voltage directly to my AGM voltage chart 12.46v should be around 75-78% charged, however the app reports this as 52%, which means the battery alerts will be off. If i select a standard SLA battery and disable the user SOC algorithm then the SOC seems a a lot more accurate. Maybe this is something that can be fixed in an app update. Unlike the BM6 the battery alerts can not be changed, they are fixed at 20 and 70%. I would have liked to have been able to move these along the scale to provide me with custom based alerts. I also own a professional battery health tester, and when i compare this battery monitor to the testing device it is quite far off in relation to the SOC. The app will send regular notifications to your phone advising you of the SOC which again is useful - especially if they were a bit more accurate. I also tried this monitor in my vehicle and had the same issues, voltage pretty accurate, SOC not so. In summary i do really like this device, it is super convenient to be able to monitor the battery from my phone. The Bluetooth range is also very good. I have the battery upstairs and i can easily get a connection from my lounge. Would i recommend this device to others? I actually would - just don't rely heavily on the SOC function, especially if you have an AGM batter which has slightly higher voltages than a standard SLA battery. I hope that a future app update will fix the algorithm that the device uses to calculate the charge levels. Review Update - digging deeper into the BM2 app i did find a custom battery setting which allows you to set charge levels based on voltage. Having amended in 10% intervals the SOC is now a little better but for some reason it is still out on the data parameters i inputted. Perhaps the algorithm is AI and is learning, and hopefully it will improve in time. I hope that you found my review helpful

I’ve been getting regular low battery warnings on my Landrover for years. I’m now on my 3rd battery in 7 years. I decided to get this battery monitor to see if I can find the problem. It was easy to connect, and download and set up the app with the battery type (in my case AGM), within just a few minutes. After a day of use I have been able to see that my charging voltage is OK. But for some reason when my car is sitting unused on the drive, I can see that periodically something is automatically switching on, using power for a few minutes, and switching off again – only to constantly repeat this cycle every few minutes. So I now have something to investigate. My only criticism of this device is that the Bluetooth range is not that good, only 2 or 3 metres from the car at best. But I suppose that is to be expected as the battery and monitor are tucked away in the engine compartment surrounded by metal. I can however just get a Bluetooth signal from it if I put my phone indoors on the window ledge right next to the drive, and of course it works fine inside the car. Overall a very useful bit of kit if you are experiencing battery problems, I wish I’d got one years ago…

I have just bought a 2nd one of these I was so impressed. The first one monitors the starter battery on my elderly campervan. This latest one monitors the leisure battery. I use the "BatteryMonitor" app to view graphs & instantaneous voltages. I can choose to be sent notifications if the voltage drops to a level I have set as too low . We have on street parking and this is much better than having to stand in the street in the rain with the van bonnet up with a multimeter in hand. It was very easy to fit. I am really pleased. Life made a bit easier.

My Alfa Romeo Giulia is very suspect to battery low voltages and will have all sorts of problems and errors. This little device is dead easy to fit and gives me an indication of the battery state before I make an attempt to start the car and cause all sorts of errors and warnings. If it reports the battery is low I can use my little lithium booster box and since I have done this I have not had a starting issue or any warnings. I have people say that it will cause the battery to discharge and yes it will over a vast period of time but then again so will the radio and the clock and the alarm. The current draw on this item is in milliamps and so the parasitic current draw is negligible.

In some ways this is a 5 star item but I felt I could only give 3 stars as I returned it. The hardware consists of a very small box with wires coming out of it ending in spade connectors. Fitting it just entails connecting it to your battery terminals. The device is accessed using the BM2 app which has not been updated in some time. The app can be used with more than one device but a dedicated multidevice app is available BM3. BM3 has an additional cost of £8.99 which is disproprotionaly high, but I bought it anyway. The BM3 app has a number of problems so was returned to the Play store. Monitoring battery voltage using BM2 worked very well and assessing the effect of starting the car and alternator worked when triggered in the app. Data was not exportable from the BM2 app. I returned the item as I found the app simplistic and limited. The BM3 app would have been better suited if it had not had bugs, was not an additional £8.99 and looked like it was still being supported. I replaced it with a more expensive device that requires no manual triggering, monitors multiple cars and makes data available for export, Ancell BM300 pro.

Great monitor for my 12 volt battery on my BMW i3 would recommend very easy to fit

Produit bien facile à utilisé

Considerando che da poco che l’ho montato fornisce dati importanti sullo stato della batteria! Io l’ho montato su un camper e sono sempre in libera, in questo periodo sempre al freddo in montagna e sapere quando mettere in moto per evitare cali eccessivi è una manna dal cielo!!!

Funziona benissimo, anche l'app. Ne ho acquistato subito un secondo per la seconda auto di casa.

Le moniteur permet d'avoir de nombreuses informations sur l'état de la batterie brancher sur un panneau solaire on retrouve toutes les informations sur le téléphone. Il permet ,entre autres , de surveiller la batterie lors du démarrage du véhicule.

Ne ho comprati due, uno per ogni auto di casa. Non è indispensabile ma a me non piacciono le sorprese. E' molto preciso nell'analisi e se c'è un problema nella batteria lo segnala prima di rimanere a piedi.