Question about Li-Ion drill battery

First off, let me just say, if this is in the wrong section, then feel free to move to the correct on. Now, onto business. I got tired of the old Ni-Cd drills and went to corded drills for the longest of time. A neighbor of mine let me borrow his lithium ion cordless drill, and i was hooked back on cordless drills. I bought me one, and i have a question that the manual does not answer. In the manual, it says that if the drill stops working while using, to let go of the trigger, then squeeze the trigger again. if the drill still doesn't work, then the battery is dead. it also said that the "power" remains near constant throughout the life of the battery, until it dies and then needs to be recharged. my question is, when the battery gets this low to where it just stops, is the battery still in the "safe" zone? cause with the Ni-Cd, you could run it down until the battery was completely dead. but with the lithium ion, when it "dies" and no longer will run, is it still in the "safe" zone, meaning that it wasn't ran completely? I'm hoping that it has a "fail safe" to where it won't let you run it down to dead flat. I hope i'm explaining myself clear enough on what i mean. Sorta like how an old incan flashlight will run until the batteries are fully exhausted and the light is very dim, but the old digital camera's will flash a "low battery" alert, however they still have some life left in them.

Simply just stick back on charge, the cells are quite hardy with no memory issues and certainly far better than the ni-cd ones. Those needed to be used ideally till the battery was drained down and then charged back up. No topping off which shortens the life of the ni-cd. The lithium fueled drills can be topped back off at any point for next time without any memory issues.

If i use any of mine for a couple of mins i tend to leave the battery's alone, however once used a few times it gets put on charge for next time. Basically i wont top off for a couple of mins use.
Having a spare is handy to swap over whilst the other is on charge

I tried to catch a ryobi lithium pack I dropped. I ended up slinging it about 30 feet and bounced it off of concrete. It no longer worked so I dissected it.

It was 5 18650 cells in series and had some pretty significant circuitry for charge and discharge. Per cell voltage and at least one temp sensor. The drop had popped a surface mount resistor off the board which is what killed it.

Lithium packs for cordless stuff are pretty robust.

Yes, the whole not having memory is another thing i love about li-ion drills. I've been using this drill now for a few weeks, and i do believe it does have some kind of low voltage protection. Some of the days when the weather isn't cooperative, i only run the drill down to maybe half. but on days when the weather is good, i'm using the drill all the way do, to what i believe is the low voltage protection. cause when i've been working it all day, and it gets low, and i drive a 2 inch wood screw in, about half way the drill will just stop. I press the trigger in and out, and it won't work anymore until i charge it. So, i am guessing that when it does that, it triggered the low voltage protection, and stopped the drill from running the battery down any further. Sometimes it will "die" when i'm putting the screw in, and working the trigger in and out doesn't do anything, but after about 10 seconds, it will then work again, albeit weak, so i guess that it's just low, and going "in and out" of the low voltage protection. But i am happy with it, and get a long run time out of it, even though the battery that came with my drill is just the basic low capacity battery labelled the "compact" battery. There is an option to buy a higher capacity battery. But i'm so glad i tried a li-ion drill.

The reason why they say to let go of the trigger, then squeeze the trigger again is that when you max out what the drill can do, instead of bogging down and smoking the drill, it shuts off to protect the motor and battery. I know Ridgid drills do this, Milwaukee drills will give you a flashing warning on the battery tester as an added warning. I'm not sure what other companies have this overload protection. I'm pretty sure Makita and Dewalt don't have this feature, because I see them get smoked all the time at work. The batteries have overdischarge protection so as long as you don't keep trying to use them several times after the tool shuts down, the battery should be good. I've found that the 2 amp compact batteries and the 4,5, and 6 amp full sized batteries tend to last much longer than the 1.5 amp compacts and 3 amp full sized batteries as for number of charges. For Milwaukee, the good batteries are rated for 2,000 charges. I'm pretty sure that Milwaukee, Ridgid, Bosch, Makita, Dewalt, and probably even Ryobi use the same Samsung 18650 cells for their better batteries. Go with the higher capacity batteries. They don't just have more capacity per charge, but last 2-4 times longer than the lower capacity batteries that use older technology cells. If you're worried about running the batteries down, get a drill or battery with a built in battery tester. These are on most of the 18 volt batteries and 12 volt drills nowadays. Also, if you can handle some noise, impact drivers run screws in much faster and with less power. My 12 volt Milwaukee Fuel Impact Driver will do the work of an 18 volt drill for running in screws without twisting my arm off. For large screws and bolts a 18 volt Ridgid Gen5X Impact Driver beats just about anything else. Go with a brushless drill and that battery will last you twice as long.

I think what you're referring to is called low voltage cutoff. On February of 2015, I bought myself some li-ion tools and 2 batteries. On July of the same year, I had some free time, and helped a family member work on an old house on his property. We worked 10 days in a row to get done. Each day, I ran both batteries down to the cut off point, and then charged them up when I got home. When it hits the cut off, my drill completely stops, and will not work again at all, until the battery is recharged. And in this case, I ran both batteries down to the cut off point, 10 times in a row, and each battery is still working fine to this day. Now, I haven't ran them down that far (to the cut off) since then. I've ran them down a couple times to where the drill or saw started to get weak, but never low enough to where the cut off kicks in. So yeah, the batteries SHOULD have a low voltage cut off, that will shut it down and prevent you from running it down to where it will cause irreversible damage. Now, i'm not sure if running it down to the voltage cut off every time is good for the long term battery health or not, because they say that lithium ion batteries don't really like full charges and benefit better if you only run them down half way. But, rest assured that the battery SHOULD cut off to prevent you from damaging it.

Heh heh heh, I went through the same thing: annoyed at NiCd cells that were ALWAYS dead, and lost capacity with every use; back to cords to save my sanity; borrowed a few *good* cordless tools with lithium cells (in my case Dewalt), and never looked back.

As previous posters describe, those battery packs are built like laptop battery packs, with intelligent circuitry that monitors and protects the cells from over-discharge. On one hand, it's annoying that a battery will suddenly give out without warning, but on the other hand, you're getting 100% power until it does so. If you think the sudden shut-off is annoying, try cutting plywood with a cordless circular saw that's only producing half as much torque as you need.

Hooked on Fenix said:

The reason why they say to let go of the trigger, then squeeze the trigger again is that when you max out what the drill can do, instead of bogging down and smoking the drill, it shuts off to protect the motor and battery. I know Ridgid drills do this, Milwaukee drills will give you a flashing warning on the battery tester as an added warning. I'm not sure what other companies have this overload protection. I'm pretty sure Makita and Dewalt don't have this feature, because I see them get smoked all the time at work.

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I'm not sure if your coworkers are using the newer Dewalt 20V Max XR batteries, but that what I've got, and they do have overload protection. I hit it a few times drilling a bunch of holes into 30-year-old concrete slab, my compact hammer drill would suddenly conk out; wait a few seconds for it to cool down and it would run again, at least enough to get the drill out. Slap it onto the charger, in half hour it was good as new. The Dewalt charger also does have a temperature warning and delay, both for overheated and too-cold batteries.

One advantage perhaps of nicad over the liion packs is total battery life. Liion cells used or not have about a 5 year lifetime. I have an older nicad drill using a 7 year old battery that i have NEVER partial charged. It holds a charge admirably even sitting for 3 or 4 months unused even now. This being said, number of charge cycles is another matter as i dont use mine all the time so for me, nicad works better.