Hi all, id like to know if charging my mtx 838 on the rapid charger and then taking out for the day and then returning it to the charger with out fully discharging it, will reduce life. Do i need to run the batt down before every charge? Once a week? Or at all?
Thanks for the help
Nick Dap
up keeping of Nicad Batt's
Moderator: Queue Moderator
Run it down till you get a battery warning! Not all the way down! Putting it back in the charger half-discharged (lets say) might develop a memory! Even though motorola says there new batteries don't develop a memory???On 2002-01-12 08:59, Nickdap wrote:
Hi all, id like to know if charging my mtx 838 on the rapid charger and then taking out for the day and then returning it to the charger with out fully discharging it, will reduce life. Do i need to run the batt down before every charge? Once a week? Or at all?
Thanks for the help
Nick Dap
Also the rapid charger (what kind) smartcharger? intellcharger? is supposed to determine how much a battery needs to be recharged? On our new radios, the batteries, are lasting less than a year..but were checking that out! And you have a 1 yr. warrenty..maybe we got a bad batch? motorola is looking into it. As long as they replace them free before the year is up! Ed (they don't make them like they used to)
Hi:
I will not say I know everything about
Ni-Cads, but I do service more than 1000
per year.
I have all of the latest BMS, and Analyzers
Motorola makes, and a few others:
Here is what I have discovered.
TO DAYS ( NI-CADS ) are NOT the same as the
Older ones which were mostly supplied by
Union Carbide in the 70's
Some of these older Ni-Cads lasted 4 to 5 Years, and sometimes even longer.
=======================================
To days Ni-Cads are being made to last 500
Charge / Discharge Cycles.
They say these newer batteries give better
performance of the current Cycle of the battery....Personally, I think its nothing more than developing a market so a person
has to BUY a new battery every 1 to 1-1/2 years.
I still have some batteries made in the Mid
1980's for MT500's that work as well today, as when they were new. ( that's years ago)
Within these cycles depending on the battery
one can generally get 90% of rated capacity
after a full charge...And the battery IS NOT
fully charged when the Green Light appears.
It requires another 3 to 5 hours for 100%
Charge ( depending on the Battery and Charger)
Sometimes, one gets lucky, and gets a group
of primary cells that are better than others,
but that is more the exception than the rule.
In which case, the battery will have a longer
lifetime.
If you [ do not ] use your radio daily, its best to fully charge the battery, and place it in a dry, average temp environment.
Recharge the Battery 1 or 2 days prior to use.
If you use your battery only for a few hours, it is NOT recommended that you use
your charger as a radio stand....If you do, that will be 1 charge / Discharge cycle event.
If one does that 3 times a day, your battery
will be exhausted in less than 1 year.
Analyzers will many times " Restore" the battery for a short time depending on the
Quality of the cells...
But I have always been amazed that Motorola
would make a 2200.00 ( Not a miss-print ) Analyzer for a 35.00-100.00 battery.
Users that have 1000's of batteries would have to have a full time employee addressing
Battery Condition all the time.....
Persons like myself desire to give back a
REPAIRED radio with a Known good Battery, as
the battery many times can be a fault for a
poor performing radio. ( outside of a major
repair )
A bit costly, but its good support for the
customer
Anyhow, just a few thoughts from me...
MS
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-12 14:32 ]</font>
I will not say I know everything about
Ni-Cads, but I do service more than 1000
per year.
I have all of the latest BMS, and Analyzers
Motorola makes, and a few others:
Here is what I have discovered.
TO DAYS ( NI-CADS ) are NOT the same as the
Older ones which were mostly supplied by
Union Carbide in the 70's
Some of these older Ni-Cads lasted 4 to 5 Years, and sometimes even longer.
=======================================
To days Ni-Cads are being made to last 500
Charge / Discharge Cycles.
They say these newer batteries give better
performance of the current Cycle of the battery....Personally, I think its nothing more than developing a market so a person
has to BUY a new battery every 1 to 1-1/2 years.
I still have some batteries made in the Mid
1980's for MT500's that work as well today, as when they were new. ( that's years ago)
Within these cycles depending on the battery
one can generally get 90% of rated capacity
after a full charge...And the battery IS NOT
fully charged when the Green Light appears.
It requires another 3 to 5 hours for 100%
Charge ( depending on the Battery and Charger)
Sometimes, one gets lucky, and gets a group
of primary cells that are better than others,
but that is more the exception than the rule.
In which case, the battery will have a longer
lifetime.
If you [ do not ] use your radio daily, its best to fully charge the battery, and place it in a dry, average temp environment.
Recharge the Battery 1 or 2 days prior to use.
If you use your battery only for a few hours, it is NOT recommended that you use
your charger as a radio stand....If you do, that will be 1 charge / Discharge cycle event.
If one does that 3 times a day, your battery
will be exhausted in less than 1 year.
Analyzers will many times " Restore" the battery for a short time depending on the
Quality of the cells...
But I have always been amazed that Motorola
would make a 2200.00 ( Not a miss-print ) Analyzer for a 35.00-100.00 battery.
Users that have 1000's of batteries would have to have a full time employee addressing
Battery Condition all the time.....
Persons like myself desire to give back a
REPAIRED radio with a Known good Battery, as
the battery many times can be a fault for a
poor performing radio. ( outside of a major
repair )
A bit costly, but its good support for the
customer
Anyhow, just a few thoughts from me...
MS
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-12 14:32 ]</font>
I have noticed, sometimes 1 hr-rapid chargers (Saber-type for example) showing the green light after only 50-55 mins of charging time, even the (brandnew) battery is NOT fully charged. Nobody has the time and nerve, to sit in front of the charger, looking at the clock to check, if his battery is really charging 60mins. If this happens 3 or 4 times, the battery always charging for only 50-55 mins. The result is reduced performance of the battery.On 2002-01-12 14:29, [email protected] wrote:
Hi:
I will not say I know everything about
Ni-Cads, but I do service more than 1000
per year.
I have all of the latest BMS, and Analyzers
Motorola makes, and a few others:
Here is what I have discovered.
TO DAYS ( NI-CADS ) are NOT the same as the
Older ones which were mostly supplied by
Union Carbide in the 70's
Some of these older Ni-Cads lasted 4 to 5 Years, and sometimes even longer.
=======================================
To days Ni-Cads are being made to last 500
Charge / Discharge Cycles.
They say these newer batteries give better
performance of the current Cycle of the battery....Personally, I think its nothing more than developing a market so a person
has to BUY a new battery every 1 to 1-1/2 years.
I still have some batteries made in the Mid
1980's for MT500's that work as well today, as when they were new. ( that's years ago)
Within these cycles depending on the battery
one can generally get 90% of rated capacity
after a full charge...And the battery IS NOT
fully charged when the Green Light appears.
It requires another 3 to 5 hours for 100%
Charge ( depending on the Battery and Charger)
Sometimes, one gets lucky, and gets a group
of primary cells that are better than others,
but that is more the exception than the rule.
In which case, the battery will have a longer
lifetime.
If you [ do not ] use your radio daily, its best to fully charge the battery, and place it in a dry, average temp environment.
Recharge the Battery 1 or 2 days prior to use.
If you use your battery only for a few hours, it is NOT recommended that you use
your charger as a radio stand....If you do, that will be 1 charge / Discharge cycle event.
If one does that 3 times a day, your battery
will be exhausted in less than 1 year.
Analyzers will many times " Restore" the battery for a short time depending on the
Quality of the cells...
But I have always been amazed that Motorola
would make a 2200.00 ( Not a miss-print ) Analyzer for a 35.00-100.00 battery.
Users that have 1000's of batteries would have to have a full time employee addressing
Battery Condition all the time.....
Persons like myself desire to give back a
REPAIRED radio with a Known good Battery, as
the battery many times can be a fault for a
poor performing radio. ( outside of a major
repair )
A bit costly, but its good support for the
customer
Anyhow, just a few thoughts from me...
MS
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-12 14:32 ]</font>
Last edited by Nand on Sun Jan 18, 2004 6:24 am, edited 1 time in total.
Monty,On 2002-01-12 14:29, [email protected] wrote:
If you [ do not ] use your radio daily, its best to fully charge the battery, and place it in a dry, average temp environment.
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-12 14:32 ]</font>
An excellent overview, but I disagree with the above advice. If one is not going to use a battery for a period of time, it should be stored in a DIScharged state in order to prevent gas buildup.
By the way, a refridgerator is an excellent storage place. We keep our new inventory right next to the lunches and we've had very good results with "new" batteries that are over a year old. However, make sure the battery comes up to room temperature in a dry (low humidty) location before charging.
PRR
Sounds like were all in the ballpark! I would like to hear any comments about Nickle Metal Hydride batteries And, Lithium Ion Batteries!
Since I also claim not to know everything about batteries!
Comments on Storage/Charging/Quality/ anything else? Should we just keep posting here? or start a New post!
"we learn something new every day!"
Since I also claim not to know everything about batteries!
Comments on Storage/Charging/Quality/ anything else? Should we just keep posting here? or start a New post!
"we learn something new every day!"
Last edited by Nand on Sun Jan 18, 2004 6:25 am, edited 1 time in total.
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-12 19:23 ]</font>On 2002-01-12 15:55, PRR wrote:Monty,On 2002-01-12 14:29, [email protected] wrote:
If you [ do not ] use your radio daily, its best to fully charge the battery, and place it in a dry, average temp environment.
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-12 14:32 ]</font>
An excellent overview, but I disagree with the above advice. If one is not going to use a battery for a period of time, it should be stored in a DIScharged state in order to prevent gas buildup.
==========================================
<b>With all respects to who may have the
best results, this really should be taken
into consideration"
Although one can have ( and ) chose any method of storage, results may vary from
type, age, and condition of a battery.
I have found that charging a Ni-Cad fully, and then letting it " Discharge" over a period of time is Much easier on the battery
as it has a " Time Period" to de-charge and
will remain in a " Active" state during the
discharge cycle.
Draining a battery and then allowing it to become cold will in fact cause irreversible
damage to the chemicals inside, not to mention damage to the primary cell casing.
Again, although some may wish to do this, its against established recommendations for battery storage. ( in any state of condition )
Note:
Main reason for this is due to the Extreme
temp range the battery may be subject too.
25 degree to 75-80 degree changes Wow !
That is to say when a Battery is subject to
varying " Cold " temps, the battery will shrink, then upon returning to normal temps, it will " expand ", and thus ultimately cause battery leakage.
I have taken enough of the Batteries apart
from customers who live in " Cold " environments to see what happens to a battery
when its used in a Cold area of the country, then placed into a Rapid Charger and then
" Heated Up ". This being done over and over
again will shorten the battery life.
Even at Normal temps, Rapid Charging the battery is not all that great !!</b>
==========================================
By the way, a refrigerator is an excellent storage place. We keep our new inventory right next to the lunches and we've had very good results with "new" batteries that are over a year old. However, make sure the battery comes up to room temperature in a dry (low humidty) location before charging.
===========================================
<b>Again, one can chose their own approach, however, not all refrigerators may be the same, and many develop a Humid Atmosphere and that to can cause corrosion on battery
contacts. Many times mosture will collect
on the surface of the battery contacts and
will damage the plated surface....Ever see
" Water " droplets form on items inside
a refrigerator?
Depending on how well a Battery is SEALED, water can even get inside the battery case.
==========================================
Anyhow, not to say any ones persons advice
is good or bad, the above just has been based
on " years " of trial and error, and who knows....Litium Ion, Metal-Nickel Hydride batteries have their own degree of perfrormance.
Monty</b>
============================================
PRR
Hello All,
Great topic!
Replacement Ni-Cad Battery Packs we use in Aircraft Emergency Lighting are stored under refrigeration and are completely sealed in a plastic bag to prevent entry of moisture. If I remember correctly they expire after a year. They are then returned to the Battery Shop. All the ones I ever used from the freezer had a full charge voltage present at the terminals.
And on a different but similar topic I read an article by Bob Grove, Editor of "Monitoring Times", and he stated that the memory effect never existed in Ni-Cads. He said this term first came about due to a malfunction in a NASA spacecraft that caused a slow discharge on the Ni-Cad but it was not due to the battery. It was from an unknown external load that they later discovered. I wish he could have elaborated more because this "memory effect" term is thrown all over the place with respect to the charge behavior of Ni-Cads.
Anyone ever heard of that explanation?
Eddie
N4UMJ
<font size=-1>[ This Message was edited by: N4UMJ on 2002-01-12 21:08 ]</font>
Great topic!
Replacement Ni-Cad Battery Packs we use in Aircraft Emergency Lighting are stored under refrigeration and are completely sealed in a plastic bag to prevent entry of moisture. If I remember correctly they expire after a year. They are then returned to the Battery Shop. All the ones I ever used from the freezer had a full charge voltage present at the terminals.
And on a different but similar topic I read an article by Bob Grove, Editor of "Monitoring Times", and he stated that the memory effect never existed in Ni-Cads. He said this term first came about due to a malfunction in a NASA spacecraft that caused a slow discharge on the Ni-Cad but it was not due to the battery. It was from an unknown external load that they later discovered. I wish he could have elaborated more because this "memory effect" term is thrown all over the place with respect to the charge behavior of Ni-Cads.
Anyone ever heard of that explanation?
Eddie
N4UMJ
<font size=-1>[ This Message was edited by: N4UMJ on 2002-01-12 21:08 ]</font>
Never heard of that story about NASA. Lots of NiCad users will experience that "memory effect" at sometime. Some articles on batteries say that the phenomenon does not happen. "Under proper conditions" does the "memory effect" happen according to one article I read, I think it was on eham.net.
The difference between NiCad's and NiMH's are: NiCad batteries are prone to the "memory effect" and discharge more slowly in storage.
NiMH batteries do not have the "memory effect," can be charged whenever you want, and discharge quicker in storage.
If you practice good battery care, any battery you use will last you a long time.
The difference between NiCad's and NiMH's are: NiCad batteries are prone to the "memory effect" and discharge more slowly in storage.
NiMH batteries do not have the "memory effect," can be charged whenever you want, and discharge quicker in storage.
If you practice good battery care, any battery you use will last you a long time.
What! With all this wealth of info above! If its just a rapid charger. (See Monty's post above) for a full charge "depending on the battery & charger" 3-5 hrs. after the green light is on! (Since I'm home, I'm not up on the charger NTN1171A, so if someone else is?) "go for it" but you have the basics now!
There will be a test next Friday! take care! Ed
There will be a test next Friday! take care! Ed
Hi:
With respects to leaving your radio
in the charging stand, you really should
not have to worry all that much....If you
return the radio to the charger many times
during the day, you can either install a On/Off switch, or unplug it from the wall, or
if you have a " Wall Switch" that controls a
outlet, I do recommend persons use that.
However, since most batteries will only last
1-1/2 years, get the most out of the battery
within that period, buy a new one, and your radio will perform very well
Outside of that, get a dummy stand....
Also as a note of interest:
Not to get into a pissing contest, but
this is a example of what the engineers
have to say about ion batteries. As quoted
from the book.
It may be applicable to Ni-Cads too.
=========================================
Simple Guidelines
Charge the Li-ion often, except before a long storage. Avoid repeated deep discharges.
Keep the Li-ion battery cool. Prevent storage in a hot car. <b><h2>Never freeze a battery.</h2></b>
Avoid purchasing spare Li-ion batteries for later use. Observe manufacturing date when purchasing. Do not buy old stock, even if sold at clearance prices
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-13 03:13 ]</font>
With respects to leaving your radio
in the charging stand, you really should
not have to worry all that much....If you
return the radio to the charger many times
during the day, you can either install a On/Off switch, or unplug it from the wall, or
if you have a " Wall Switch" that controls a
outlet, I do recommend persons use that.
However, since most batteries will only last
1-1/2 years, get the most out of the battery
within that period, buy a new one, and your radio will perform very well
Outside of that, get a dummy stand....
Also as a note of interest:
Not to get into a pissing contest, but
this is a example of what the engineers
have to say about ion batteries. As quoted
from the book.
It may be applicable to Ni-Cads too.
=========================================
Simple Guidelines
Charge the Li-ion often, except before a long storage. Avoid repeated deep discharges.
Keep the Li-ion battery cool. Prevent storage in a hot car. <b><h2>Never freeze a battery.</h2></b>
Avoid purchasing spare Li-ion batteries for later use. Observe manufacturing date when purchasing. Do not buy old stock, even if sold at clearance prices
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-13 03:13 ]</font>
Thanks Ed, and thanks [email protected]. Yes well its been great reading all the posts. I'll be studing for friday.
Catch ya guys
Nick
Catch ya guys
Nick
Some of the Motorola "Rapid" chargers had (still do)a problem that they would overcharge a battery if left in the charger for more than 2 to 3 hours total. This was due to the "compete" or trickle charge rate being too high, usally 1/10C or higher causing the battery to stay hot. Heat and/or over charge are the number one battery killers.
We have modified hundreds or more "Rapid Rate" chargers to reduce the trickle charge rate to 1/20C or less. "C" refers to the charge rate for a specific battery and is usally expressed in MHR or milliampere hours. One C would be 1000 mhr for a battery rated at 1000 miliamp hours. So a safe trickle rate is one twentyth or 50 milliamps. The rate at which the charger "trickles or "Complete" is still charging the battery depends on how long the battery stays in the charger. Typically I set the rate at 1/20 for a Rapid charger that the battery stays in for 6 to 8 hours, and 1/40 for ten to 20 hrs.
For a standard charger they charge at 1/10 C for 12 to 16 hours and are much easier on the battery.
Moral to the question DO NOT leave the battery in the charger, and do not charge it if it still has a a one half charge or more left in it.
Just like people, If you over eat (charge) and do not work you get fat! If you work, you get to eat (charge)!!!!!
We have modified hundreds or more "Rapid Rate" chargers to reduce the trickle charge rate to 1/20C or less. "C" refers to the charge rate for a specific battery and is usally expressed in MHR or milliampere hours. One C would be 1000 mhr for a battery rated at 1000 miliamp hours. So a safe trickle rate is one twentyth or 50 milliamps. The rate at which the charger "trickles or "Complete" is still charging the battery depends on how long the battery stays in the charger. Typically I set the rate at 1/20 for a Rapid charger that the battery stays in for 6 to 8 hours, and 1/40 for ten to 20 hrs.
For a standard charger they charge at 1/10 C for 12 to 16 hours and are much easier on the battery.
Moral to the question DO NOT leave the battery in the charger, and do not charge it if it still has a a one half charge or more left in it.
Just like people, If you over eat (charge) and do not work you get fat! If you work, you get to eat (charge)!!!!!
Interesting.... we kept the Saber and MX (Nicads only sealed in the bags in the freezer and had great luck. I have had great success with a charger made by Advance Tech. The chargers go into a pulse /check stage when in maintenance mode and only charges the battery when it senses a drop below the value. I still have MX and Saber/Stx batteries running from 90-96 ande lasting entire day. Motorola puts their name on the and sells them as a conditioning charger. If voltage is in the 7.0 range you can switch pockets and use it for STX, Saber, MX etc. Also have a 10 volt unit and 4 slot gang chargers. Enjoyed everybodies input and learned something as always.
Hi:
Talk about getting eaten by a can
of worms !!
Anyhow, many of my comments, and I guess
I should have kept quiet, is from reading
data from Battery OEMS's, and general practice....THEY ARE ONLY SUGGESTIONS, and
to be used at the viewers discretion.
Many of my view points are subject to specific interpretation at the time a comment is made, and is not intended to offend, or rebut another person(s) view....
But to clarify my comment on the ion batteries, that was from the Web Site, and
they are the ones who really should have that
credit....I too have a Extra Ion battery for
my Cell Phone, and well, they too last about
1-2 years....and then I get ripped off again.
What is really sad is one can buy a 60 lb
Car battery for less than 1/2 of some of these Two-Way HT batteries...Explain that one?
<h2><b>All these mfg's have done is create
a bunch of battery addicts and a in-exhaustable demand...</h2></b>
MS
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-14 14:13 ]</font>
Talk about getting eaten by a can
of worms !!
Anyhow, many of my comments, and I guess
I should have kept quiet, is from reading
data from Battery OEMS's, and general practice....THEY ARE ONLY SUGGESTIONS, and
to be used at the viewers discretion.
Many of my view points are subject to specific interpretation at the time a comment is made, and is not intended to offend, or rebut another person(s) view....
But to clarify my comment on the ion batteries, that was from the Web Site, and
they are the ones who really should have that
credit....I too have a Extra Ion battery for
my Cell Phone, and well, they too last about
1-2 years....and then I get ripped off again.
What is really sad is one can buy a 60 lb
Car battery for less than 1/2 of some of these Two-Way HT batteries...Explain that one?
<h2><b>All these mfg's have done is create
a bunch of battery addicts and a in-exhaustable demand...</h2></b>
MS
<font size=-1>[ This Message was edited by: [email protected] on 2002-01-14 14:13 ]</font>
Hmm, sounds like drug dealing. "Psst, want some NiCad. Dime bag, real cheap."On 2002-01-14 14:10, [email protected] wrote:
>All these mfg's have done is create
a bunch of battery addicts and a in-exhaustable demand...</h2></b>
MS
>[ This Message was edited by: [email protected] on 2002-01-14 14:13 ]</font>
Anyway, my point about the refridgerator needs some clarification:
- The interior temperature should be in the 40's ideally, and not subject to constant opening of the door. The condensation inside a refridgerator is usually do to outside humid air condensing when the door is opened excessively, or a freezer section not in a fully seperate compartment. A refridgerator by it's very nature is a dehumidifier (for the interior anyway).
- The battery temperature range given by the manufacturers is the operating temperature range, not necessarily storage. Most batteries should have no problem being stored at 32 - 50 degrees, much less operated in that range. As I said originally, make sure you bring the battery up to room temperature - passively - prior to charging. This will avoid any of the problems you've seen when your customer takes a battery out of their truck after a -10 degree night and immediately puts it into the charger.
Your mileage may vary.
PRR
Well? I got shot down a bit by my
own staff....In talking about batteries
( eegads, should be talking about girl
friends ) here is something I found to
support PRR position on batteries in a
Refrigerator.
======================================
Keep batteries in a cool and dry storage area. Refrigerators are recommended, but freezers must be avoided because most battery chemistries are not suited for storage in sub-freezing temperatures. When refrigerated, the battery should be placed in a plastic bag to protect it against condensation.
The NiCd battery can be stored unattended for five years and longer. For best results, a NiCd should be fully charged, then discharged to zero volts. If this procedure is impractical, a discharge to 1V/cell is acceptable. A fully charged NiCd that is allowed to self-discharge during storage is subject to crystalline formation (memory
Hope that helps
I guess I am just biased because my
old kluker reefer tends to frezze Milk
from time to time
MS
own staff....In talking about batteries
( eegads, should be talking about girl
friends ) here is something I found to
support PRR position on batteries in a
Refrigerator.
======================================
Keep batteries in a cool and dry storage area. Refrigerators are recommended, but freezers must be avoided because most battery chemistries are not suited for storage in sub-freezing temperatures. When refrigerated, the battery should be placed in a plastic bag to protect it against condensation.
The NiCd battery can be stored unattended for five years and longer. For best results, a NiCd should be fully charged, then discharged to zero volts. If this procedure is impractical, a discharge to 1V/cell is acceptable. A fully charged NiCd that is allowed to self-discharge during storage is subject to crystalline formation (memory
Hope that helps
I guess I am just biased because my
old kluker reefer tends to frezze Milk
from time to time
MS
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Code3Response
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OK, so I have a question: I leave my HT1000 with one of its batteries sitting in its rapid charger almost 24/7 
:(:( mostly its off, but maybe 3/4 hours a day its on, as its sitting on my desk. Is there any kind of charger that will figure out the battery is chargerd and shut down or go to super-trickle mode while it stays in its charger? Right now, the model number of my charger is NTN7029A. Thanks!
:(:( mostly its off, but maybe 3/4 hours a day its on, as its sitting on my desk. Is there any kind of charger that will figure out the battery is chargerd and shut down or go to super-trickle mode while it stays in its charger? Right now, the model number of my charger is NTN7029A. Thanks!I'm with 1 adam 12 in that our department has switched most of its charging to pulse chargers by Advance Tech. They have an excellent brochure explaining their method of recharging and it seems to work well. I have also had very good results with the 777 universal charger made by Maha. It appears to be the same unit that Radio Shack is closing out at about $30 (p/n 23/250). You have to experiment with getting the contacts to work on a specific battery, but has excellent results.