# Rechargeable batt.



## Yoyizit (Jul 11, 2008)

http://en.wikipedia.org/wiki/Lithium_ion_battery
There are hyperlinks in this article to the other types of batteries.

"High drain applications such as power tools may require the battery to be able to supply a current as high as (15 h-1)C (that is, a current level that would drain the battery in 1/15 hour if sustained; e.g. 22.5 A for a battery with a capacity of 1.5 Ah)."

BTW, "the C rate" for an XX A-hr battery is XX Amps.

You should probably decide if you want 
high torque, 
high speed, 
high power or 
high energy (power over time).

For which of these is important to you you're looking to minimize cents per
in-lb, 
rpm, 
watts or 
watt-hours.

Reliability is related to how hot the drill motor gets during normal use.


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## Highlander (Mar 2, 2009)

Forget NiMH. They were supposed to be the replacement for NiCd batteries but never really took off. Generally NiMH cells have higher capacity (amperage) than NiCd but that is where the advantages stop. NiMh lose charge quicker than NiCd while on the shelf (doing nothing), and do not work in the cold. NiCd batteries have stood the test of time and are still the most popular battery. And contrary to popular belief, they do not have memory problems. The life of these batteries is varied. I have a pair which are 18 years old and I still use them. I have many others between 1 and 5 years and have yet to have a battery fail. Generally, I do not work my batteries hard, each one probably gets charged once every 2 to 4 weeks as they show a loss of power while working a tool.

Li batteries have only been out a couple of years, some companies have only started selling them for about a year. They are very popular. They lose very little charge while sitting on the shelf (there is a small chip in them, so they do consume a small amount of energy while doing nothing); after three months on the shelf, they will have no noticeable loss of charge, while NiCd or NiMh will both require charging before using if left that long. They do not slow down while in use, they maintain about the same power level right up to the point they don't deliver any power. The first time you use one, it is quite un-nerving when the power shuts off; the first reaction is the tool has broken. This shut-off is done deliberatly to prevent running the battery down too far. Li batteries are lighter than NiCd and generally have more charge (amperage).

Li batteries are more expensive than NiCD (about 2X). Don't know what the life is yet. They degrade with number of charges and also with time (non-use). The worst thing you can do that affects their life is to keep them fully charged and in a hot place; the hotter the storage temperature and the higher the charge is, the quicker the battery will degrade. A degraded battery will still work as well as a new one, but will run down quicker. Estimates that I have read would indicate a Li battery will lose half its capacity after 2 years. I have not heard of people experiencing this loss. Also there seems to be some issues with the batteries being used in cold weather, they need to be warmed up to work.

Make your choice. Both types will work well.


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## Chemist1961 (Dec 13, 2008)

I disagree with HIGHLANDER , but only on the memory issue. I used to rebuild rechargeable shavers with battery packs. Most folks dont know there are basic and high output forms of NI CADS and some will by there makeup have a longer usage due to capacity (MAH), not voltage but either way a NI CAD that is not drained and then fully recharged will fail quicker. Consatnt recharging is the killer unless fully drained but we did save some newer shavers by fully draining and recharging over night
HLs method of bweeklyy recharge occurs after full drainage, so he does it right , hence the 18 year life span and he is constantly cycling and draing his tools thru usage... 
The guys who got two years out of a shaver generally kept it plugged in daily. The same shaver but recharged every two weeks when it died would often last another customer 7-10 years with original Ni Cads. We used to tell the guys to run down their shaver, lying on a face cloth so it wouldn`t vibrate off the counter. Then recharge fully overnight, even if the green light came on after an hour. They would come back smiling,and clean shaven, more power , better shaves , longer battery life:thumbsup:
I`ve been out of the business for a while but suspect chargers and NiCads have not found a new life cycle , so charge em fully drain em fully just like HL. Itès the inconvenience of waiting to recharge that drives the tool industry to faster technology
I have a new Hitachi with NI CADS and love the torque but didn`t realise till after the fact it was NI CAD. But it was new in box at the Habitat ReStore for $60 so I kept it. Hope it goes 18 years. My old Dewalt 9 volt and Makita 7.2 are over 10 years and still ticking except for damaged batteries from cartwheels off the ladder.


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## Highlander (Mar 2, 2009)

I would caution anyone from deliberatly draining a battery too far. Once the tool stops giving you the power you want; that's the time to recharge. If you drain it too far you risk damaging the battery, and also that the charger will not recognise it as a battery. As a general rule, never take a NiCd battery down below 0.8 volt/cell (or 12 volts for an 18 volt battery). Mine usually read 17 to 18 volts when I am putting them on the charger. NOTE: an 18 volt battery straight off the charger will read about 21 volts.

As the chemist notes, 'storing' a battery on the charger is a bad habit. For a NiCd battery, the charger goes to a trickle charge mode when the green light comes on. Supposedly if you leave the battery on the charger for an extra day it will 'condition' the battery or 'top-off' any low cells. But if you leave it on too long, you will basically over-charge and permanently damage the battery. Personally I try to take mine off as soon as the green light goes on, only occasionally forgetting and leaving it overnight.

Memory: Classic NiCd memory occurs when a battery is repeatedly run down to the same point at the same rate of discharge and then placed on the charger. With power tools this doesn't happen, and therfore the battery cannot develop memory. However, NiCds do develop crystals which reduces the capacity of the cells, and this is sometimes called memory. These crystals form as a result of shallow discharge (thus the reason you should normally use the battery until it indicates low power). Most of this effect can be reversed by the periodic 'full' discharge of the battery. When I say full, I mean to when the tools show a loss of power.


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## Thurman (Feb 9, 2009)

For some interesting reading on re-chargeable batteries and the types available go to www.primecell.com. I use them for my battery rebuilds and the rebuilt ones outlast the new ones that come with the units I have. Just my 2¢ worth, David


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## PaliBob (Jun 11, 2008)

Thurman said:


> Just my 2¢ worth, David



Congratulations on the 2¢ and for knowing how to input special characters.
ps I use http://www.batteriesplus.com/

Their Local for me (in Culver City)
.


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## vsheetz (Sep 28, 2008)

I love my newer tools with Lithium-ion, when compared to my older with NiCads. The Lithium-ion retain their charge when sitting unused, last longer doing the work, etc.


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## micromind (Mar 9, 2008)

One negative I've seen with the L-ion is they have very low capacity when cold. 

I have Milwaukee V-18s, the sawzall will cut 1/2" emt for 1/2 a day on one charge when its warm, but only 2 or 3 cuts when cold. 

By cold I mean below about 35F. 

If I remember to bring them inside when it's cold (I rarely do!!) they work much better. 

Rob


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## Thurman (Feb 9, 2009)

Gee Bob, thanks for the pat on the back. Are you saying "batteries plus" does rebuilds on NiCad batteries? I looked at their site but didn't go deep into it. If they do, and they are closer to you, then that's what it is all about. With Primecell, they are in PA. and I am in GA. so they work for me. Don't doubt that if I find a comparable place, even on the west coast, that I will look into them in the future. Thanks, David


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## vsheetz (Sep 28, 2008)

micromind said:


> One negative I've seen with the L-ion is they have very low capacity when cold.


Ah, now I have yet another reason why I like living in San Diego!


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## jimofoz (Jul 21, 2009)

In our area, Michigan, BatteriesPlus does battery pack rebuilds. I've also bought nicads with them attaching tabs I need. and their web site states they build custom battery packs as well.


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## macro01 (Aug 11, 2009)

has anyone tried lithium polymer batteries? are they good?


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## rusty baker (Feb 13, 2009)

Be aware that lithion batteries can be dangerous. The airline workers are trying to stop them being shipped by plane, They can spontaneously get hot and have cause three airplane fires over the past few months.


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## Highlander (Mar 2, 2009)

_"and have cause three airplane fires over the past few months"_

I don't believe you. Name one incident that I can look up.

I agree that you don't want to mess around with building Lithium-ion batteries. You need the protection devices and correct chargers; not for the 'ameteur'.


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## rusty baker (Feb 13, 2009)

http://findarticles.com/p/articles/mi_m0UBT/is_29_18/ai_n6280925/ this is just one of the artihttp://www.startribune.com/local/54787532.html?elr=KArksi8cyaiUo8cyaiUiD3aPc:_Yyc:aU7DYaGEP7vDEh7PiUscles
Maybe this is easier
The world's largest pilots union said Tuesday it wants bulk shipments of lithium batteries and products containing the batteries immediately banned from passenger and cargo planes because they can start a fire.
The Federal Aviation Administration said it is not prepared to take emergency action on the issue.
In seeking a federal ban, the Air Line Pilots Association pointed to three incidents since June in which lithium battery shipments apparently caused fires aboard U.S. planes.
On Aug. 14, a fire in a shipment of 1,000 e-cigarettes - a battery-powered device that provides inhaled doses of nicotine - was discovered in the cargo compartment of a plane after it landed at Minneapolis-St. Paul International Airport. Each cigarette contained a rechargeable lithium-ion battery.
In another instance, a package of cell phone batteries shipped from Michigan to the Dominican Republican was found smoking and smoldering after a United Parcel Service plane landed in Santo Domingo on July 15. The package documentation indicated "used batteries - non-haz."
A burned package containing a lithium-ion "bicycle-power device" was discovered in the cargo of a UPS flight from Ontario, Calif., to Honolulu on June 18, the union said.
"The evidence of a clear and present danger is mounting," Mark Rogers, director of the union's dangerous good program, said in a statement. "We need an immediate ban on these dangerous goods to protect airline passengers, crews and cargo."
The union emphasized that it is not seeking a ban on passengers carrying electronic devices containing lithium batteries onto planes, such as laptop computers, cell phones, and cameras. Instead, the union's concern is with cargo containing multiple batteries, either loose or inside products.
If a battery short-circuits, it can catch fire and that fire can ignite other batteries.
John Prater, the union's president, said in a letter to Cynthia Douglass, acting deputy administrator of the Pipeline and Hazardous Materials Safety Administration, that an immediate ban on shipments is necessary until the agency can develop regulations for safe packaging of the batteries for transport.
He noted that Douglass told a House panel this spring that the safety administration is working on new regulations for the shipment of lithium batteries. However, he said that if the government doesn't act quickly, the union will ask Congress to step in.
Officials for the safety administration didn't immediately return a phone call seeking comment.
Federal Aviation Administration spokesman Paul Takemoto said aviation officials are working with the safety administration on regulations to address the problem.
"At this point in time we're not prepared to take emergency action, but we're watching the situation very closely," Takemoto said.
Prater said the three recent incidents are similar to a Feb. 7, 2006, incident in which a UPS DC-8 made an emergency landing at Philadelphia International Airport after the flight crew detected smoke in the cargo hold, which worsened as the plane descended. The plane landed safely and the crew escaped with minor injuries, but the plane and most of the cargo were destroyed.
"We have been most fortunate that the lithium-ion battery malfunctions (in the three recent incidents) didn't cause an accident, but luck is not a sound safety strategy," Prater said.
The Federal Aviation Administration no longer permits large, pallet-size shipments of lithium-metal batteries on passenger planes. Airline passengers are not allowed to pack loose lithium batteries in checked luggage. Consumer electronics containing lithium batteries are still allowed in carry-on and checked luggage. However, passengers are limited to two spare lithium batteries in carry-on baggage.

*Posted on Tue, Aug. 25, 2009 11:54 AM*


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## Highlander (Mar 2, 2009)

That incident happened in 1999, not the last 3 months, and was the result of dropped pallet. I still don't believe there have been any incidents in the recent past on airplanes.

Li-ion batteries have become much safer over the years for handling, and their use is widespread. A lot of people sit on them daily as they drive their Toyota Prius' around.

They can be dangerous, if you don't have the correct protections and overcharge them, they can self heat to about 4,000 F and explode and ignite almost anything they come in contact with (part of the problem with the laptop batteries a while back). Also, if they should happen to be in a fire, the material burns at extremely high temperatures, feeding the fire, and making it more intense. I believe this is the reason strict controls are in place for transporting the batteries; it's not the fire risk, but what it would contribute to a fire making the fire more intense.


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## rusty baker (Feb 13, 2009)

In seeking a federal ban, the Air Line Pilots Association pointed to three incidents since June in which lithium battery shipments apparently caused fires aboard U.S. planes. This staement is in the above article.


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## brokenknee (Dec 13, 2008)

Not sure about the fake cigarette thing, but all reputable builders now use either a PCM or PCB ( protection circuit module or board). They learned this from the laptop and cell phone fires. 

Any type of battery can be dangerous, basic precautions should be observed. You should never leave any battery on the charger for extended periods of time without monitoring them. 

It is true that lithium ion batteries vent with flame and could cause a fire; however that risk is now extremely low with the advancement of battery management technology. 

IMHO I think that lithium ion is a good choice for the professional or the heavy do it yourselfer. The lighter weight is one of the biggest pluses. If you are going to be carrying the tool around all day that extra couple pounds makes a huge differance.

Down side is the cost, and the battery packs them-self do not last as long as Ni-Cad. I am not talking about holding a charge on the shelf, I am talking about usable life of the battery pack if both are treated properly.


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## ehoez (May 12, 2008)

i know this thread is from 2009... but wanted to see whats everyone comments on it 2 years later.. after we tried and tested Li-on


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