My Makita Bl 1830 battery pack , just stopped working . I only used for 3 months . I paid $300 for a set of batteries and a drill/ driver ,and i can use that much . Need help or replace the battery . I hope warranty cover it . $100 for a battery is to expensive Peter

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you should be able to, but it will eventually burn the battery up. but only if it slips into the charger with no force from you.

Why can't you buy the 230 volt DC18RA charger in europe (amazon.europe country) and use it. I had the same issue yet i burned out the fuse in the 110 volt DC18RA charger because i plugged it into the wall just using an adaptor. Lesson learned. Therefore, my first solution was that i bought a converter from 220V-to 110 Volt. This showed me that my charger was done. So instead of getting another 110 volt charger sent here to Europe from Canada, I returned the converter and have on order a 230 volt input DC18RA charger from amazon.de which has the same 7.2-18V output. I have been told this will work yet the fear, and I don't know why, is that it will burn out the batteries in a year or so. It is difficult getting specific information from Makita, but I hope it all works out. Best of Luck for you

You can try to put it in the freezer for 24 hours. When you remove it let it set at room temperature for at least a day before you try to recharge it. I don't understand why this works but I had someone reccomend this to me many years ago on my cell phone battery and it worked . I hope this helps you. Thanks

If the charge count on the batteries is under 300, Makita will replace them. Makita has a known defect in this battery that causes the battery to shut down before it is dead. So as of now they are exchanging ones with low use.

If they are truly defective and makita won't replace, you have to open them, find the dead cell or blown fuse, and replace. Search youtube makita battery for a video on repairing this battery. But once the red and green lights on the charger flash, the the battery can't be charged on a Makita charger -- it's been locked. So use a third party charger.

I can't find the 1402 battery listed on the Makita website. What is the tool catalog number and I will find you a bettery that way. You can buy online at Makitatools.com and also they have a locator to find one locally that you can use. Let me know if you need more assistance.

Pardonnez moi parsque ma francais est tres mal! If you have been a bad boy and managed to short the battery by using it for non-proscribed purposes, the fusible link will blow (kind of like a fuse) To fix it, open up the battery (use a Torx 10 security bit, or a small flathead in a pinch) On the battery connection nearest the spring-loaded white catch there is a small bridge of metal with a hole in the center. If this is melted you can solder it back together by sanding the two pieces and putting a glob of solder on them. This will void your warranty (duh!) and remove the battery's fuse protection, but it WILL work again. If the link is intact and nothing else is obviously wrong, you almost certainly have a bad cell. I recommend pulling out the bad cell ( it will be the one that does not read between 2.5 - 4 vdc) and replacing it with one from another dud battery- this requires some fudging and re-soldering. Or do what I did, pull the cell, toss the electronics and the short pink wire, add a cigarette lighter socket and voila! you have a portable power supply giving around 14 volts. Charge it up by wiring two cigarette lighter male ends together (check polarity , + to + and - to -) and plug it into your car, but only while it is running or you will be charging your car battery with it! Hope that helps.
Matt Binns GiantGlobes.com

Unfortunately, Makita’s li-ion battery packs have a design flaw. After having the same problem with my two batteries, I took it apart and saw the problem immediately. You see each battery pack has ten li-ion battery cells and a circuit board with a memory chip witch holds the charging history of the battery pack. But that memory chip constantly draws power from 2 of the 10 batteries. The current it draws is very small but if you consider it over 8 month or more, the power drain becomes very significant. You end up with a battery pack with 8 still fully charged battery cells and 2 drained battery cells. When you put this battery pack in the charger, it detects weak battery cells, assumes they are defective and refuses to charge. To avoid this problem you should charge your battery pack often, even if you haven't used it, every two months should be ok.
I suspect that Makita doesn’t make these battery packs, they make power tools, good ones too. Buy Makita should definitely have a few words with their supplier before they become a liability!

Unfortunately, Makita’s li-ion battery packs have a design flaw. After having the same problem with my two batteries, I took it apart and saw the problem immediately. You see each battery pack has ten li-ion battery cells and a circuit board with a memory chip witch holds the charging history of the battery pack. But that memory chip constantly draws power from 2 of the 10 batteries. The current it draws is very small but if you consider it over 6 month or more, the power drain becomes very significant. You end up with a battery pack with 8 still fully charged battery cells and 2 drained battery cells. When you put this battery pack in the charger, it detects weak battery cells, assumes they are defective and refuses to charge. To avoid this problem you should charge your battery pack often, even if you haven't used it, every two months should be ok.
I suspect that Makita doesn’t make these battery packs, they make power tools, good ones too. But Makita should definitely have a few words with their supplier before they become a liability!