FNIRSI HRM-10 Voltage Internal Resistance Battery Tester，Battery Voltage Meter for Types of Batteries, Car Battery Tester, AAA AA Battery, 100V 200Ω, Digital Battery Analyzer for Household Automotive

I've owned this tool for a couple of months, and it has proven itself many times.-----BEFORE YOU BUY ONE, read this:This particular listing is just the tool and a set of Kelvin clips, which are fine for batteries with tabs or posts, but are a pain to use for any cylindrical cell. They make a cylindrical cell holder accessory for the HRM-10, but the only way to get one (as of July 2025) is to order directly from FNIRSI from China.Luckily, it seems they listed another version of the same tool, but it includes the cylindrical battery holder AND a set of Kelvin-style probes. Trust me, it's well worth paying more to get the complete kit with those accessories. I wish they had this option when I bought my HRM-10!-----Okay, now the review:Using a multimeter to check a battery serves most people well enough; if it shows somewhere near the expected voltage, it's most likely a good battery. But voltage is only half the story -- if the battery has a high internal resistance, it won't perform well in high-power devices (if it even works at all) nor last very long, and in the case of a rechargeable battery, it won't recharge fully (or the battery charger might not "see" it). That's where having a tool like this comes in handy.As for my use, I have a large pile of unprotected 18650 and 21700 cells, and ever so often I'll find one of them dead. I have a "smart" charger for these batteries, and sometimes it acts like I didn't just insert a battery. When I put that battery in the HRM-10 and see that its internal resistance is several ohms, then I know why the charger can't "see" it, and I can discard the battery without any doubts about whether it was a savable battery with a false reading.Over the past few years, I've picked up a FNIRSI tool here and there, and now that I own about three of their tools, I've got to say that I am supremely impressed with their design, functionality, material and build quality, and craftsmanship. The HRM-10 is no exception -- it feels great in your hand, and there's nothing cheap about it.If you're an electronics hobbyist who works with batteries, this is an invaluable tool. But make sure you get the one that includes the battery holder!

Got this with a $15.00 "coupon" offer so it was just the right price. I am building my own 21700 packs for FPV wings and quads so having the ability to match cells by internal resistance is key. Fnirsi for me has been a solid brand. The quality is definitely there.

The meter works really well, but I highly recommend purchasing the pogo pin tips depending on what you are measuring. Strangely, the meter would sometimes get the measurements completely wrong and would require a restart. It would show >100v on a 4v cell for some reason.

This is a gem of a device for a hobbyist. They are giving you a near lab grade voltage and resistance measuring meter here for a crazy inexpensive price. The nice gator clip leads top it off. Put it into a manual resistance mode and see for yourself. I could use this to make a very precise meter shunt because I can get a very precise resistance measurement across a short conductor, then see that reading decrease moving the probe a millimeter over. You are getting at least a couple extra digits of measurement you're not going to find on a DMM twice the cost or more. And yes, you can measure voltage and internal resistance of a battery at the same time with it.

Mejor de lo que esperaba

Excelente para realizar las mediciones en las celdas de Liion, lamentablemente el cable de pruebas demasiado corto.

WHY DO THEY SELL CHINESE LANGUAGE ONLY IN THE USA ?EVERYTHING IS IN CHINESE !IF A COMPANY CARES SO LITTLE FOR THEIR CUSTOMERS THEY DON'T EVEN OFFER LANGUAGE OPTION THEN THIS CAN GO BACK TO THE CHOPSTICK PARADISE IT CAME FROM !IT WILL PROBABLY BREAK IN A FEW MONTHS ANYWAY ....LIKE THE REST OF THE FINE MERCHANDISE MADE THERE

I almost sent the FNIRSI HRM-10 Voltage Internal Resistance Battery Tester back because of the absolutely terrible user manual. After turning it on, and maybe my fault, I was stuck in the Chinese language. I could use the meter but I could not change the time and date or get to English. I managed to find my way to the setup menu, but of course it was in Chinese. I then remembered reading a review prior to purchase here on Amazon that gave some helpful hints. So I went back to the reviews and there was was. Thank you Roger.Following Roger's instructions I scrolled down to #8, which is language, and was able to select English. Then I was able to scroll to time and date and make the needed changes.How accurate is this little gem? Beats me, but you gotta have faith in something. Four stars instead of five.