MINI-9RL Multi-Battery Tester

Awesome product, easy to use.

I love the fact that it uses a pulsed load to evaluate the battery condition, not just reading the voltage like cheaper testers. However, since I won't use this very often, and it requires four AAA batteries, I'll worry about them leaking out during storage. I sort of wish it had an external power source, but instead, I'll just remove the batt's when the unit isn't being used. Btw, it does a great job at evaluating Ni-MH batteries, which is one of the main reasons I chose it.

Nicest feature is that this tester goes off after using so no more wasted batteries! I was always leaving my old one turned on accidentally. This one is slightly bulky but easy to use and tests multi-batteries. I accidentally purchased the smaller of this brand and found it doesn't test many types of today's battery. (Do not buy the smaller of this brand. Waste of money)I would love this if it was easier to store.

You need a battery tester that actually puts a load on the battery to get an accurate testing. This is a great little tester. I have 2 of them. I will eventually have to take the plunge and buy the big one. You won't regret it you will reach for it all the time and it will pay for itself in batteries. So just do it already.

SMALL UNIT THE GETS THE JOB DONE. JUST PURCHASED AND KEEP ONE ON EACH FLOOR. SEPARATES THE GOOD FROM THE BAD VERY EASILY AND SAVES THE USER A TON OF MONEY ON BATTERIES. QUALITY BUILT.

The cheaper testers are practically worthless. Often batteries that stopped working still tested in the good range with them. This tester puts the battery under a slight load while testing it, a much more accurate process. I intially cringed at the price but I'm glad I got it.

I feel guilty giving only a 3-star rating to the MINI-9RL, but the headline notes an important part of why I can't give it 4 stars. Where's 3.5 when you need it? Anyway, on with the review... The MINI-9RL battery checker is a handy tool for a difficult job: assessing a cell's or battery's state of charge without draining it remains tricky. Though the MINI-9RL can often provide significant improvement compared to simple meters, sometimes a simple meter may still "win". The MINI-9RL is smaller than I'd guessed, a bit smaller than the palm of my hand. Its small size and stowable test lead make it easy to store and carry, but... Small size costs an important feature: the inability to properly check "1.5 V" cylindrical lithium cells is significant. I'd gladly let the MINI-9RL "grow" a bit to get that one additional capability. Omitting a popular chemistry from one of the testable formats ("'1.5 V' cylindrical cell") seems like a misstep. Hint 1: The instructions are correct to suggest running multiple tests, and for more than one reason. Not only can a cell or battery "wake up" or "die down" when "disturbed", some simply produce noisier results than others. Multiple tests are the way to "see what's going on". Hint 2: Note the MINI-9RL has an "On" button, not a "Power" button. You _can't_ turn it off: it does that for you after a couple minutes of inactivity. Well, OK, you can "turn it off" by pulling a cell from the battery compartment, but what's your hurry? To try out the MINI-9RL, I scrounged around for various spare batteries, "used up" batteries awaiting recycling, and battery-operated things. I found more than three dozen cells and batteries to check. (Wow, where did all those come from?) Where suitable, I then used one of several battery analyzers to discover the accuracy or inaccuracy of the MINI-9RL's assessments. I've summarized my observations by cell chemistry, below. NiMH (Nickel/Metal Hydride; AA, AAA, and "9 V"): The MINI-9RL did a surprisingly good job checking this otherwise difficult-to-assess chemistry. A couple of the AA cells and one of the "9 V" batteries exhibited bizarre discharge behaviors on their respective analyzers, but every cell or battery that didn't offer simply baffling behavior ended up revealing a state of charge similar to the MINI-9RL's indication. Alkaline (AA and "9 V"): Well, into every test effort some surprise must fall. A pack of overaged Eveready Gold AA's slated for recycling fooled the MINI-9RL, eliciting 80% charge estimates and then delivering more like 25%. Even after being drained on a battery analyzer and then rested for a few days, these sneaky cells generally read 60% on the MINI-9RL, with one 80% reading punctuating the observations. A recheck on the battery analyzer revealed they were in fact (still) empty. Here's a case where a simple meter "wins": open-circuit voltages in the low 1.4's would have cast suspicion on these empty cells. "9 V" batteries gave better results: empty read as empty, while nonempty seemed to elicit some nonsevere optimism. A couple Duracell thermochromic checkers agreed with the MINI-9RL in calling an aged standby battery "full". I tried the thermochromic checkers for this instance because I didn't want to waste the in-service battery by discharging it fully on an analyzer. Lithium ("9 V"): Nearly untried. I lacked discharged and significantly-used "9 V" lithium batteries. A virtually-unused standby-service unit properly read "full". Lithium Mistests ("AA" and "AAA"): The MINI-9RL properly tests only NiMH and alkaline cylindrical cells, but this is a learning effort! In case you want to misuse the MINI-9RL for "1.5 V" lithium/iron disulfide (Li/FeS2) cells (e.g.: Energizer Ultimate Lithium), you face the question of "_how_ dead?" the cells might be. Checking various "used up" cells I found the MINI-9RL's NiMH position more nearly accurate, declaring "sufficiently dead" cells empty, but still foolable: some "less dead" cells were able to trick the MINI-9RL into reading "full", but then delivered only a trivial fraction of rated capacity on a battery analyzer. So, if you must misuse the equipment then expect to get what you deserve, but at least try the NiMH position in hope of "less inaccurate" results.

Someone recommended that the poles be changed so that the negative side of the battery was used to make contact and the wire probe used to make a positive connection. I agree this would be a great improvement and make the device much easier to use. Labeling should also be updated to include some of the newer Ion type batteries.

Indispensable pour une vrai évaluation.