BL1850B

This 5 AH appears to be same size and weight as my old 3AH Makita battery that was starting to show weakness. I popped it in the charger and it was ready in about 45 min. Zero bars charge out of the box - but all topped off now. Gave it a try in the Makita circular saw and works well. Satisfied with my purchase. Haven't tested the power vs the 3AH nor the duration of the charge but I expect it to be excellent.Love the addition of the charge level meter - makes it easy to pick up and see if its ready to go. A little more than a Dewalt OEM 4 AH i got recently but still in the ballpark of what OEM's cost these days at around $80.Pleased with purchase ... I now have to be careful I don't go and justify additional Makita tools to use the battery.

Worked great

Battery last for couple of days. Doesn’t take very to charge. I have dropped it couple times and has tooken no damage

The makita batteries last do much longer than the knock off brands! It’s worth it to spend the extra money!!!

As advertised

4 starts only because mine was not sealed in original packaging. It was in a ziplock bag like the kind you use in your kitchen. No where in the description does it say this is a open item, returned, or refurbished item. so 4 stars. The price & quality of the battery saved this review.Battery looks new. No scuffs or marks showing use.Battery charged and works as it should. I tested it hard in my weed trimmer and it easily out performed my 4Ah OEM battery.Battery is identical to my expensive OEM Makita batteries. I cant tell any difference in any way.I Will buy more of these.Not sure why it did not come in OEM packaging. Not sure where these come from or if they are refurbished or open returns. They do perform as they should and the price is excellent.

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

Excellent product. Lasts about 1.5 time the 4.0 Ah.