Lithium-Ion batteries

[TruckTech]

I got my new Makita cordless tool set today from the MAC guy, and he said to make sure I let the batteries charge at least overnight, and under no circumstances should I just let it charge until the charger says its good (at least just the first time). He said that doing that is one of the worst things you can do to Lithium-Ion batteries.

The manual says that after the initial "fast charge" is completed (it did in about 25 minutes), it will go into a trickle charge mode for a max of 24 hrs.

So, anyone, is this necessary?

 

[FNFS2000]

not sure on the makita but with any of them I have used when the lights go out or change colors or stop blinking there is not more juice flowing and leaving them on does not good or harm. With old(and cheap new) systems they never stop charging and going too long with cook your batteries.

 

[malibu101]

Bash me for saying this but........
What do the instructions say?

 

[Bo Heck]

Bash me for saying this but........
What do the instructions say?

Great point, do what the manual says, not the MAC dude, doubt he has an engineering degree. If the manual says nothing about it, you can do what he says if it makes you feel better, it's not going to hurt it. From my experience though, worst thing you can do for batteries is leave them on the charger after they're charged. Most chargers say they have some sort of overcharge protection or something but Li-ion batteries should not discharge over time like the NiCad ones so trickle charging them after fully charging them is pointless.

 

[TruckTech]

The Makita manual says nothing about it. It does however, not saying anything against it either. It mearly says, like I said before that after the battery is fully charged, it goes into a trickle charge mode for a max of 24 hrs. It says that this is for maintaining the full charge only and does not overcharge the batteries. It even referes to it as "maintenance charge" elsewhere.

It does mention a "conditioning charge", but it seems to say that the charger will do this automatically, and only if it seems the battery is used in extreme conditions or if its used until its completely dead.

Thats all I guess. I suppose I wont worry about it.

 

[tonyvlx]

Got the same set. Best tools i ever bought.Love the impact gun

 

[daveblank]

The Makita manual says nothing about it. It does however, not saying anything against it either. It mearly says, like I said before that after the battery is fully charged, it goes into a trickle charge mode for a max of 24 hrs. It says that this is for maintaining the full charge only and does not overcharge the batteries. It even referes to it as "maintenance charge" elsewhere.

It does mention a "conditioning charge", but it seems to say that the charger will do this automatically, and only if it seems the battery is used in extreme conditions or if its used until its completely dead.

Thats all I guess. I suppose I wont worry about it.

Keep the battery on the charger till you need it.

 

[swduncan]

The advice the driver gave sounds like nicad or nimh advice. Nicads had memory, and I think nimh often got the same rap by association.

I've read that lithium ion batteries require a lot of smarts in the charger because it's hard to check the charge state by votage drop or current (the deltas on both are small) - they're basically impossible to abuse from the charging perspective because of this. I have seen multiple references to lithium ion batteries being sensitive to excessive discharge, however most everything I have with lion batteries seems to have a sophisticated battery meter that warns when the battery needs charging.

My wife's usually-dead iphone (first generation bought in January of '08) seems none the worse for wear.

I've found several manuals that make repeated mention of charging the battery completely before use. I suspect this is to reduce customer service calls more than anything. People get exicted with their new toy, don't charge it much, then get upset that it has short battery life. The battery has to have been charged before it shipped, because it has _some_ power.

Otherwise, as far as I'm concerned we've finally reached battery nirvana for most applications, and it's called lithium ion.

 

[TruckTech]

Got the same set. Best tools i ever bought.Love the impact gun

Yah. I finally forced myself to buy it. Ive been borrowing another techs Makita impact about every other day for the last month. 3 people in my shop have this same kit, and 2 have the kit with the driver and radio, and everyone is really happy with their makitas. 2 techs use SO, and while I have the new 1/2" SO at home and love it, their 3/8 is just too heavy and bulky for what I needed at work.

Keep the battery on the charger till you need it.

I plan on just using one battery and keeping one on the charger at all times, trading off every day. I dont think Ill need both batteries at once unless I really end up liking that flashlight.

 

[Bolster]

This is from memory so... you should verify but... I recall studying this out and learning that:

LiIon does not have a certain number of cycles in it [EDIT: Wrong! When I wrote this I thought Li-Ion aged by time only, but It ages by both time and cycles, see my research below], so you can recharge it often and even at half charge if you like [EDIT: Correct]. IIRC you don't want to run LiIons way down. [EDIT: Correct.] Charge them up whenever you get a chance. [EDIT: the jury's still out on that one, but mostly correct.]

NiMH on the other hand, has a certain number of cycles in it. [EDIT: and they also have a little memory effect.] So you DON'T want to charge them until they are close to depleted. One of the worst things you can do to a NiMH is leave the batt in the charger, because it just sits there and burns through cycles. [EDIT: Correct.]

I remember the safest option for batteries in general is to charge to full (especially the first time) and thereafter remove from the charger after it's full.

 

[Bustawrench]

LiIon does not have a certain number of cycles in it, so you can recharge it often and even at half charge if you like. IIRC you don't want to run LiIons down. Charge them up whenever you get a chance.

.

Milwaukee's LIon batteries have a small circuit board in them that counts how many times the battery has been charged. When it gets to 2,000, or 5 years from the first charge..........it decides that it's time to die and will not let the battery charge, ever again.

I forget the reasoning behind this.........something about the batteries becomeing unstable and starting fires............probably BS to sell more batteries.

 

[Bustawrench]

Otherwise, as far as I'm concerned we've finally reached battery nirvana for most applications, and it's called lithium ion.

LIon is Da Bomb.................unless they are stored in a work truck, or unheated space...........my Bosch tools are completely dead below 40*F. Warm the battery up for five minutes on the defroster vent and it's good as new.

Kind of a PIA when you're working on rooftop units in January in NJ.

 

[Bolster]

Some interesting quotes:

Lithium-ion is a very clean system and does not need priming as nickel-based batteries do. The 1st charge is no different to the 5th or the 50th charge. Stickers instructing to charge the battery for 8 hours or more for the first time may be a leftover from the nickel battery days.

The charge time of most chargers is about 3 hours....The charge efficiency is 99.9% and the battery remains cool during charge...No trickle charge is applied because lithium-ion is unable to absorb overcharge...Depending on the battery, a topping charge may be repeated once every 20 days...Extreme low voltage must be prevented.

a new lithium-ion pack does not need cycling through charging and discharging. Priming will make little difference because the maximum capacity of lithium-ion is available right from the beginning. Neither does a full discharge improve the capacity of a faded pack. However, a full discharge/charge will reset the digital circuit of a 'smart' battery to improve the state-of-charge estimation

http://www.batteryuniversity.com/partone-12.htm

It is important to note that trickle charging is not acceptable for lithium batteries.

http://www.powerstream.com/li.htm

NiCad - Requires discharging for long life; Memory effect
NiMH - Poor low temperature performance, Low cycle life.
LiIon - No discharge required; Can be recharged in any condition

http://www.urbanfox.tv/articles/batteries/b1batteries.html

NiCD - A disadvantage with NiCd is its memory effect, which requires periodic discharge to prevent charging problems. Advantages include its simple charge characteristics and its ability to accept a high number of charge/discharge cycles

NiMH - NiMH offers about 30% to 40% higher energy density than NiCd. Also, NiMH batteries are less prone to memory effects.

LiIon - Li-ion’s life expectancy is 300 charge/discharge cycles, with 50% capacity at 500 cycles. (Calls my remark above into question).

http://electronicdesign.com/Articles/Index.cfm?AD=1&ArticleID=20737

Lithium ion (Li-Ion) disadvantages:
-- has a shelf life based on life of battery, not related to charge or charge time
-- can sometimes erupt or explode in high heat - hot cars, direct sunlight, etc, or sometimes after tampering. a more dangerous battery than the others
-- permanent damage to battery if stored at too-low discharge level, so be careful and keep these charged well

Nickel metal hydride (NiMH) disadvantages:
-- fewer life cycles compared to NiCad
-- shorter run time
-- performs the worst in cold temperatures, so keep that in mind if you plan to use tools powered by NiMH outdoors in cold weather
-- higher self-discharge level than NiCad
-- voltage drop at near-discharged levels

Nickel cadmium (NiCad) disadvantages:
-- Heavy, making it harder to use for longer periods of time
-- May suffer from 'Memory Effect' or 'False Bottom Effect' if constantly discharged half-way and then recharged (wiki pedia)

http://www.streetdirectory.com/travel_guide/159640/technology/nimh_vs_nicad_vs_li_ion.html

As you can see, conflicting advice regarding Li-Ion. Notice Bustawrench's post also leaves the question open regarding the life of a Li-Ion battery...is it time, or is it cycles? Or both?

 

[nissan_crawler]

Bosch says NOT to charge them up before storing, and leave them low. In short, do whatever the manufacturer says.

 

[d33pt]

what is the difference between the white makita tools and the blue ones? seems like the white ones are homeowner grade and blue is pro?

 

[Bolster]

Sorry to keep posting, but the question of how to best charge Li-Ion has got me interested, and I keep doing research. More quotes:

"A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges...Aging of lithium-ion is an issue that is often ignored. A lithium-ion battery in use typically lasts between 2-3 years. The capacity loss manifests itself in increased internal resistance caused by oxidation. Eventually, the cell resistance reaches a point where the pack can no longer deliver the stored energy although the battery may still have ample charge...The worst condition is keeping a fully charged battery at elevated temperatures...If possible, store the battery in a cool place at about a 40% state-of-charge...some lithium-ion batteries fail due to excessive low discharge...

Simple Guidelines:

- Avoid frequent full discharges because this puts additional strain on the battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory. (In this respect, lithium-ion differs from nickel-based batteries.) Short battery life in a laptop is mainly cause by heat rather than charge / discharge patterns.

- Batteries with fuel gauge (laptops) should be calibrated by applying a deliberate full discharge once every 30 charges. Running the pack down in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate and in some cases cut off the device prematurely.

- Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.

- Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)

- Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing dates. Do not buy old stock, even if sold at clearance prices.

- If you have a spare lithium-ion battery, use one to the fullest and keep the other cool by placing it in the refrigerator. Do not freeze the battery. For best results, store the battery at 40% state-of-charge."

http://www.batteryuniversity.com/parttwo-34.htm

So there it is again. According to this source, Li-Ion ages both through cycles, AND through time. So it's confusing whether you want to be recharging it frequently, because each charge is a cycle. Yet, the recommendation for Li-Ion is to charge the battery more often, to not let it get run down like you do with NiCad and NiMH.

 

[X1 Mike]

Got the same set. Best tools i ever bought.Love the impact gun

+1
Could not imagine working without them.

 

[Mr.Nutcase]

I got my new Makita cordless tool set today from the MAC guy, and he said to make sure I let the batteries charge at least overnight, and under no circumstances should I just let it charge until the charger says its good (at least just the first time). He said that doing that is one of the worst things you can do to Lithium-Ion batteries.

The manual says that after the initial "fast charge" is completed (it did in about 25 minutes), it will go into a trickle charge mode for a max of 24 hrs.

So, anyone, is this necessary?

How much did you pay?

 

[PCW]

I just bought a Milwaukee M18 Cordless 1/2 Impact Kit, came with the charger, 2 batteries that are warranted for 5 years. My owner's manual just stated to change the battery fully before using, did not say for 24 hrs etc...

PCW

 

[TruckTech]

How much did you pay?

$500 + $15 shipping + $35 tax

Could have bought it off the internet for about $430 IIRC, but I didnt have the money on hand, so the MAC truck it was!



I got to use them finally today. Started a clutch in a Chevy 7500 and the 3/8 impact was GREAT for pulling the driveline (didnt have enough grunt for the rusted carrier bearing bolts, but my MG725 took care of them nicely ), pulling the crossmemers, exhaust, doghouse, clamps, and all sorts of other ****!

On the batteries though, I had one on the charger for about 3 hours, then put the other on the charger for about 12 hours overnight. This morning I pulled the overnight one off and put the other one back on, and started using it. After another 5 or so hours of charging, I needed my impact and my flashlight, so I pulled the other one off the charger and started using it (after a total of 8 hours on the charger). According to the Makita manual, a fully charged 18 volt battery should let the flashlight run for 240 minutes. After using it for about 90 minutes the flashlight started turning off on me. If I turned it back on, it would stay running for about a minute or so then turn off. Another tech with the same kit said that was becasue the battery needed recharging.

Faulty battery?

EDIT: I should note that after my battery was having issues, I borrowed one from the aforementioned tech after he had been using it on his on and off all day, and it worked fine for the next hour, then I left.