Makita BL1850B-2 18V LXT Lithium-Ion 5.0Ah Battery, 2/pk, Black

I have nothing but nice things to say about this battery. It is almost identical in dimensions and weight to the BL1830's, but adds an additional 2 amp hours of runtime, the battery capacity gauge, and Star protection. The battery capacity gauge works well. Activating it requires depressing a small push-button switch on the back of the battery. This is a plastic "bubble" style magnetic switch found on devices like kitchen timers. This style of switch is not the most durable, and seems to be the weak link in what is otherwise a very well-made product. So far so good, though, so perhaps this will not be an issue over the life of the battery. Star protection is Makita's name for an internal circuit that will not let you overheat the battery, or run the battery down to such a complete state of discharge that it cannot be recharged, which can be an issue with some lithium battery systems, like Makita's own BL1830 batteries.The best feature of this battery over an 1830 is the warranty: 3 years instead of just one. That makes this a pretty reasonable investment for any regular user. Also note that the additional capacity should mean fewer recharge cycles, and thus longer life.While I have nothing but nice things to say about this battery, I do have some less-nice thing to say about Makita. The Star protection is great, but they sold non-Star tools and batteries for a number of years, leaving a lot of customers such as myself with a significant investment in these products. While Star protection is marketed as a feature of the new generation of tools and batteries, a more honest evaluation would be that Makita sold a tool/battery system with a significant design flaw for quite a while. This battery represents what is essentially a totally different battery system. It looks the same, is still called "LXT," and uses the same chargers, but it is physically not compatible with the old tools without warranty-voiding modification. If you have non-Star tools, you can easily take a chisel to the small tab that prevents this battery from mating with them, and this battery will power them just fine. However, this modification definitely voids the tool warranty, and might void the battery warranty as well-- these batteries do contain a memory chip, and I have not been able to find any definitive information on whether or not they log interfacing with a non-Star tool. It also means that the battery will not be protected by the Star circuitry when using that tool.I am currently "playing it safe" and using this battery only with my Star tools. I'm not quite sure what I'll do if my non-Star tools outlast my dwindling BL1830 fleet. As much as I love my Makita tools, unless Makita offers some kind of trade-up program, I have a feeling that the solution might be yellow and black.

After a couple of years in advanced homeowner class use, I have put these through the paces for long enough to share opinions. Overpriced, but they do perform. I have an older generation tool set (~ 2007?) and was able to modify them to accept these type batteries. Have had zero issues. Love the longevity and charge meter on the 5.0!

I know the title sounds like someone who works for the seller wrote it, but it's the best price I found for a makita battery. And it's a real makita battery, not a handful of AA's in a imitation shell. It works amazing with all my tools.

Mikita is a great brand, I really like the Mikita lawnmower. This was a very good price for two lithium batteries.

Great product

I think they should make them more impact resistant, like the milwaukee batteries have some rubber on them that absorbs the shock a bit

These batteries will not fit the older tools that have the black battery receiver plate without the star on it unless you file, cut or grind off the wee little tab on the tool receiver plate that keeps the battery from sliding on. I cut it off by hand using a jigsaw blade on 5 of my tools in less than 10 minutes. These older tools used the the BL1830 battery. The older tools had only two contacts instead of three like the newer tools that have the yellow receiver plate with or with out the star or black receiver plate with the star. The extra contact is so the battery and tool can communicate allowing the battery to shut off if the tool is over loaded or the battery is drained past a set point. Running a tool without this communication feature until the battery is dead will shorten battery life. Over loading a tool creates heat that is bad for the tool and battery life.The ideal situation is to use and store the batteries at room temperature as leaving them in your truck with the windows up on a 100 degree day with the windshield facing the sun is not good for them. Heat is bad for the batteries. If you have to lock them up in a situation like this, a cooler bag with an ice pack would help. On the other hand cold temperatures reduce battery capacity and using the battery when it is below 0 Fahrenheit is not ideal for battery life either. There is no memory effect with these batteries so top them off while using them and before storing them is a good idea because storing them in a discharged state is bad for battery life and like I said running the battery until it is dead is also bad. If you are going on an extended vacation have someone charge your batteries at least once every 3 months or risk harming the battery. Do not leave the batteries on the charger for ever. Take them off as soon as you can after they are charged. In the real world you have to get the job done but to the extent that you can follow these rules your batteries will last longer. I have had some BL 1830 batteries last up to 5 years but some didn't make it that long and did I follow my own advise? Not always by any means!So you might wonder why that little tab is on the tool battery receiver plate of some of the tools. It was to keep people from using the little BL1815 batteries on high drain tools. The discharge rate could be too high for the little batteries. I had to tease all this information out of the Makita tech people as there is no way they will advise cutting off the tab on your tool for all the reasons that you could imagine but they had no information as to why it would be a bad idea either which is their way of saying go ahead and do it but we don't want to know about it. All my tools are out of warranty anyway. I have seen several reports of people cutting the tab on their tools and not having any problems with using the BL1850 battery. Just keep in mind that the two electrical connector tools are not talking to the battery like the tools with three connectors so you need to be a little smarter about how you use them if you want to optimize your battery life. Do not drain the battery all the way and do not push the tool especially with a low battery. Some people have said their drills spin faster with this battery or their reciprocating saws have more power than with the BL1830 battery but I think what they are experiencing is as the battery ages and gets near the end of its life the batteries can not provide the same amperage (drain rate) or amp hours (capacity) as when they are new. If you compared the performance of this battery to a new BL1830 in a drill you should see the same rpm and of course a longer run time.You will also see reviews saying the batteries last twice as long or three times as long but again I think these people are comparing well used batteries to new ones. I am going to the charger a lot more often with my older batteries because they do not have the same capacity as when they were new. If you are comparing new batteries you should get 65% more run time as Makita advises. The warranty is now 3 years on the batteries so I imagine Makita has reason to believe the communication feature will improve battery life and that could be one of the reasons why they don't want you to use the battery with tools that do not have the third connector. Enjoy less trips to the charger

Typical Makita Quality!