How to Store Batteries

The recommended storage temperature for most batteries is 15°C (59°F); the extreme allowable temperature is –40°C to 50°C (–40°C to 122°F) for most chemistries. While lead acid must always be kept at full charge during storage, nickel- and lithium-based chemistries should be stored at around a 40 percent state-of-charge (SoC). This level minimizes age-related capacity loss while keeping the battery in operating condition and allowing self-discharge.

Finding the 40 percent SoC level is difficult because the open circuit voltage (OCV) of batteries does not lend itself well to state-of-charge estimations. For lack of better methods, voltage is nevertheless used as a rough fuel gauge indicator. The SoC of Li-ion is roughly 50 percent at 3.80V/cell and 40 percent at 3.75V/cell. Allow Li-ion to rest 90 minutes after charge or discharge before taking the voltage reading to get equilibrium.

SoC on nickel-based batteries is especially difficult to measure. A flat discharge curve, agitation after charge and discharge, and voltage change on temperature contribute to the fluctuations. Since no other estimation tool exists that is practical, and the charge level for storage is not all too critical for this chemistry, simply apply some charge if the battery is empty, and then make sure that the battery is kept in a cool and dry storage.

Storage will always cause batteries to age. Low temperature and partial SoC only slow the effect. Table 1 illustrates the recoverable capacity of lithium- and nickel-based batteries at various temperatures and charge levels over one year. The recovered capacity is defined as the available battery capacity after storage with a full charge.
 

Temperature

Lead acid

at full charge

Nickel-based

at any charge

Lithium-ion (Li-cobalt)

40% charge

100% charge

0°C

25°C

40°C

60°C

97%

90%

62%

38%
(after 6 months)

99%

97%

95%

70%

98%

96%

85%

75%

94%

80%

65%

60%
(after 3 months)

Table 1: Estimated recoverable capacity when storing a battery for one year
Elevated temperature hastens permanent capacity loss. Depending on battery type, lithium-ion is also sensitive to charge levels.

Lithium-ion batteries are often exposed to unfavorable temperatures, and these include leaving a cell phone in the hot sun or operating a laptop on the power grid. Elevated temperature and allowing the battery to sit at the maximum charge voltage for expended periods of time explains the shorter than expected battery life. Elevated temperature and excessive overcharge also stresses lead and nickel-based batteries. All batteries must have the ability to relax after charged, even when kept on float or trickle charge.

Nickel-metal-hydride can be stored for about three years. The capacity drop that occurs during storage can partially be reversed with priming. Nickel-cadmium stores well, even if the terminal voltage falls to zero volts. Field tests done by the US Air Force revealed that NiCd stored for five years still performed well after priming cycles. It is believed that priming becomes necessary if the voltage drops below 1V/cell. Primary alkaline and lithium batteries can be stored for up to 10 years with minimal capacity loss.

You can store a sealed lead acid battery for up to two years. Since all batteries gradually self-discharge over time, it is important to check the voltage and/or specific gravity, and then apply a charge when the battery falls to 70 percent state-of-charge. This is typically the case at 2.07V/cell or 12.42V for a 12V pack. (The specific gravity at 70 percent charge is roughly 1.218.) Some lead acid batteries may have different readings and it is best to check the manufacturer’s instruction manual. Low charge induces sulfation, an oxidation layer on the negative plate that inhibits current flow. Topping charge and/or cycling may restore some of the capacity losses in the early stages of sulfation.

Sulfation may prevent charging small sealed lead acid cells, such as the Cyclone by Hawker, after prolonged storage. If seemingly inactive, these batteries can often be reactivated by applying a higher than normal voltage. At first, the cell voltage under charge may go up to 5V and absorb only a small amount of current. Within two hours or so, the charging current converts the large sulfate crystals into active material, the cell resistance drops and the charge voltage gradually normalizes, and at a voltage of 2.10–2.40V the cell is able to accept a normal charge. To prevent damage, set the current limit to a very low level. Do not attempt to perform this service if the power supply does not allow setting current limiting. Read about Charging with a Power Supply.

Simple Guidelines for Storing Batteries

Caution:

When charging an SLA with over-voltage, current limiting must be applied to protect the battery. Always set the current limit to the lowest practical setting and observe the battery voltage and temperature during charge.

In case of rupture, leaking electrolyte or any other cause of exposure to the electrolyte, flush with water immediately. If eye exposure occurs, flush with water for 15 minutes and consult a physician immediately.

Wear approved gloves when touching electrolyte, lead and cadmium. On exposure to skin, flush with water immediately.
 

      

Comments

On January 11, 2011 at 9:27am
Alexander wrote:

How many times can I recharge a lithium-ion battery? I have Sansa e200 player with the lithium-ion rechargeable battery.

On February 2, 2011 at 5:47pm
Good Idea Guys wrote:

Need to Store Batteries?  Here’s how to do it safely:

1) Keep batteries in original packaging when possible.

2) Do not store new and used batteries together.

3) If a battery feels warm, it should be discarded.

Check here for 6 more battery storage tips:

http://www.buybattery.com/duracell_battery_storage.shtml

On March 5, 2011 at 3:37pm
Mark wrote:

I just started to store my Panasonic cordless drill batteries in the fridge in a food preservation vacuum bag to keep the moister out. Working ok so far??

On March 7, 2011 at 7:18pm
Bel Plews wrote:

> Never leave a nickel-based battery sitting on a charger for more than a few days.
> Prolonged trickle charge causes crystalline formation (memory).

Does this account for chargers that monitor health of the battery and apply charge when necessary?

On March 21, 2011 at 9:28pm
Matt R wrote:

One of the things that is misleading about the chart is that the voltages aren’t specified.  For example some Lithium Ion devices like my older laptop define 0% on its 6 cell as being 10.8V as opposed to a very small amount on some newer laptops.  Similar to that of my PSP where “100%” encompasses slightly above 4 volts to 4.2.  If I were to make a guess it would probably be because of USB charging is painfully slower at higher voltages.

The other is that some batteries protective circuits and other miscellaneous electronics slightly drain the battery.  Some Lithium Polymer batteries exhibit zero discharge at all.  I have an old Motorola cell phone that I haven’t charged for a few years and every once in a while I’ll turn it on and it’ll show one out of three bars…Just the way I left it.

To keep it short, assuming that 100% is 4.2V it would be theoretically impossible to hold the average device battery up there.  There are some exceptions to this but the best bet to storing them is to monitor the device’s progress every few weeks and go from there.

It would be nice to see some more info on that chart.  Especially in contrast on single cell versus multiple cell packs.

On March 25, 2011 at 4:45pm
Ty wrote:

If you’re going to be storing a rechargeable battery, store it at the 40 percent state-of-charge (SoC), and then recharge / discharge back to the 40 percent state-of-charge (SoC) every month to keep the internal batteries in good condition. Store batteries just below room temperature, more specifically at 59°F.

On June 27, 2011 at 8:08am
tom wrote:

Would storing a Li-Ion battery at 40% charge in a freezer at -18 C prolong the life more than storing it in a fridge at 5 C ?

Is it possible to store a Li-Ion at a temperature cold enough to damage it (say -25 C)? Will crystals form in the chemistry that could cause damage or a short?

Any specific concerns about condensation effects when taking a battery out of the fridge/freezer and plugging it immediately into your laptop for 1 hour of gaming (on batt power only)?

Thanks for the info! Great site!

On October 12, 2011 at 10:17pm
kitk wrote:

There used to be a procedure to drain a charged lead-acid battery, for long term storage; in effect, making it a dry-charged battery. Does anyone still living remember what that was?

On November 4, 2011 at 6:46am
Bernard Rieck wrote:

Where would be a good place to store a dead lead acid battery until they can be dispode of properly.

On November 26, 2011 at 2:25pm
Aleks wrote:

What would be better for a saving of a Lithium Ion battery: to be in every day working laptop using external power or in a fridge?

On December 7, 2011 at 8:03am
NormMonkey wrote:

@Aleks For a laptop Li-Ion battery, well, the battery would be better off in the fridge at around 40% charge.

Keep in mind that you won’t be able to use Suspend-To-Ram without a battery attached.

Many laptops allow you to set them so they don’t charge to 100% while attached.  Keeping your battery in your laptop but at 40% charge rather than 100% will prolong its life.

My battery temperature is around 30 degrees Celsius while sitting attached to my laptop on AC power neither charging nor discharging.

On December 9, 2011 at 2:01pm
Guillaume wrote:

Not sure the fridge is a great idea. Don’t forget that temperature is not the only storage criteria. High humidity environnement may affect the battery life expectancy !

On December 10, 2011 at 3:02am
Aleks wrote:

@Guillaume Thanks. Do you have better idea? If the battery is in a plastic bag?

On December 12, 2011 at 6:23am
Guillaume wrote:

Optimal storage conditions are :

Clean and dry location
Temperature below 25°C (10°C would be optimal if you want my opinion)

I dont know about your location. In my case, winter is cold (-10°C average) so I use the garage for battery storage. My garage is heated at 12°C so the humidity level is low and the temperature is good.

Keeping the battery on the laptop at 40% charge as suggest by NormMonkey could work but dont forget that the heat coming from the laptop will affect the battery so you may want to store it somewhere else.

For the bag idea, it may help to prevent dirt and other stuff to be in contact with the battery but I dont know about humidity. You might want to use the basement as it usually colder there.

On December 12, 2011 at 1:16pm
kitk wrote:

I take it that no one watching here has ever heard of dry charged batteries. If that changes, please let me know.

On December 15, 2011 at 7:19am
John Fetter wrote:

Storing a fully charged lead-acid battery at -10 degrees C is absolutely perfect. The acid will not freeze. You can go down to - 20 but don’t go too far down. Self discharge is a chemical process. It speeds up with increase in temperature, slows down with decrease. It is not linear. Lowering temp. dramatically reduces self discharge. 

Dry charged batteries were made decades ago when the industry had difficulty keeping the self discharge of batteries down. Simply charge to 100%, drain out all the acid, wash out residual acid, dry. Then seal the vents air tight. The negatives will discharge spontaneously in contact with air. When the battery is needed, refill with acid, charge. Very cumbersome. Easier to put the battery in the fridge!

On December 25, 2011 at 6:07pm
Luffy wrote:

‘Avoid freezing. Batteries freeze more easily if in discharged state.’
Do you really mean: Avoid freezing.Batteries discharge more easily if in freezed state.

On December 26, 2011 at 10:20pm
kitk wrote:

Quite right, and thank you for your advice on dry charged lead-acids. I am among those burdened with a desire to know how and why things work, much to the amusement and consternation of the bulk of the populace. There are not enough of us to go around, so at least the net allows us to offer what we know.
Thank you again.

On January 7, 2012 at 5:35pm
ritch wrote:

how long can you store AA and AAA if you have a lot of new ones

On January 12, 2012 at 4:12am
John Fetter wrote:

Ritch, Put your AA and AAA batteries in your fridge and they will stay fresh longer than storing them any other way. Some of mine have been there for more than 3 years and they come out working fine. The colder, the better but do not freeze.

On February 16, 2012 at 1:33am
Viktor Berglund wrote:

I’m writing a guide regarding the computer’s battery. Can sleep mode damage the battery capacity in a lithium-ion battery.

On February 21, 2012 at 1:20pm
Thom wrote:

When I bought a used laptop I automatically bought a new 9-cell replacement battery for it.  When my laptop arrived, I discovered that the battery that came with it was basically new and also 9-cell.  I’ve opened both batteries so I shan’t sell one.  Is it better to store one of them at 40% charge to wait for the other to go bad, or should I rotate them once a month, always storing the other at 40% and trying not to let the charge drop below 40%?

On February 21, 2012 at 3:10pm
Matt wrote:

Thom.  What kind of laptop do you have?

On February 22, 2012 at 10:25am
Thom wrote:

It’s a Thinkpad T60.  It dual boots Ubuntu 11.10 and WindowsXP, but I mainly use it for Ubuntu (I notice the predicted battery life is strangely longer under XP though).

On February 22, 2012 at 10:27am
Thom wrote:

It’s a Thinkpad T60 that dual boots Ubuntu 11.10 and WindowsXP (I use it mainly for Ubuntu but I notice a much longer predicted battery life under XP strangely).

On February 22, 2012 at 2:41pm
Matt wrote:

I would guess that, but that’s only because I use a T60 and an X31.  As for the two 9 cells what I would do is check the Power Manager and note the manufacture and the total capacity (you can check the total capacity in Ubuntu also).  Panasonic batteries in my experience tend to hold better over time because of their better construction and their microcomputer doesn’t crap out like the Sanyo’s (my 9 cell is a Sanyo and my 6 cell is a Panasonic.  So far the Panasonic seems to be more consistent and autocorrecting than the Sanyo).

It’s not too strange under XP.  If you have the ATI chipset (X1300, X1400.  Not sure the T60 has the CAD one) the power management features are enabled with the drivers.  The Ethernet drivers are also programmed to disable the interface if not in use (not sure about Ubuntu).  Your best bet is to check Thinkwiki for tips on it but not sure if it covers Ubuntu 11.1

On February 22, 2012 at 3:13pm
Thom wrote:

Right now I have the replacement in which it says is a Sony at 95.7% Capacity.  The battery that came with it is at home and is the original Lenovo/IBM.  When this computer came in the mail it was *spotless* and looked brand new (except the windows XP sticker on the keyboard is partly rubbed off).  I got quite lucky.  There wasn’t even any wear on the touchpad or keyboard, these all had the slight matte finish found on new devices.  It was supposed to have been used in a professionally capacity before it was resold by the computer shop in MA.
I installed PowerTop this morning but I’m only half sure that I’m using it correctly.  I was going to fool around with CPU Frequency Scaling Monitor but wasn’t sure if that would make a difference.  I saw something about installing proprietary drivers for the GPU.  I’m not sure how to verify but I *think* that it uses the ‘Intel Graphics Media Accelerator 950 Graphics Card’.  This is based on looking up the Product ID: 195143U.

On February 22, 2012 at 3:54pm
Matt wrote:

Yeah, the Type 1951 has the GMA945 or something like that.  As for the Sony battery I’d urge to make sure it’s not a part of the recall (if the battery was manufactured recently it should be OK).  As for the quality I do not know.  I’ve read they’re really bad but I don’t use them so I wouldn’t know.  Finish wise mine was like that but the motherboard failed 3 months into ownership.  However the keyboard, palmrest and the bezel can be removed with 9 screws and only about 5 minutes so it as skeptical as I am it could of been easily replaced.

On the Windows side most of the settings you’d want to mess around with would be in the Lenovo Power Manager or the ThinkPad Configuration Utility.  They allow for fan control as well as other controls including the optical drive speed.

On February 25, 2012 at 10:20am
HTWingNut wrote:

This information is confusing and misleading regarding the storage of batteries. I have never had any laptop Li-Ion batteries degrade 20% over the course of a year even if left installed with laptop connected to AC 100% of the time. Wondering what conditions these were tested under and how old the data is?

On February 28, 2012 at 3:58am
Peter wrote:

Can the Lifepo4 batteries can mount in any position during usage. Or any restriction of keeping it vertical as the leads always upwards.

On March 28, 2012 at 2:19am
Mark Smith wrote:

The Li-Ion battery should be good for up to 500 cycles before it starts to lose its capacity, depending on its brand and quality.

On April 12, 2012 at 7:42am
AnthonyJosephWeber wrote:

need batteries for experiments

On July 11, 2012 at 1:11pm
ramon leigh wrote:

Just some of the many reasons we need much better batteries than the crappy ones we have today.

On July 13, 2012 at 8:52am
John Fetter wrote:

Ramon - The problem is caused mainly by the people who are buying the batteries !
(1) Nowadays most people insist on buying the cheapest battery they can find to replace the one that has just worn out. Getting something at the lowest possible price apparently makes them feel clever.
(2) The cheapest batteries can only be produced by manufacturers who are willing to cut corners.
(3) Manufacturers who refuse to cut corners go out of business.
(4) The system is self perpetuating, until all the batteries on the market are junk.

On July 18, 2012 at 6:16pm
Martin wrote:

urgent…..Please help finding the answer.asap
What is the correct answer for the condition of a stored lead-acid batter does’nt full charged .Why?
a) the lead plates have crystallized
b) The lead plaes have ionized
c) the specific gravity of each cell is high
d) the voltage of each cell after chaging at its normal rate is low

Thank you very much.

On July 18, 2012 at 11:51pm
John Fetter wrote:

Martin - If your lead-acid battery has been stored for a very long time, the plates will most likely have become sulfated. That is not good. A sulfated battery refuses to accept a normal charge. There are many different types of products on the market described by their manufacturers as desulfators. Take your pick.

I stored a lead-acid battery for five years without it becoming sulfated by using the following procedure:
1. Remove caps. Empty out all the acid and store it separately.
2. Flush out the battery cells two/three times with reasonably pure water, (can use drinking water), to remove most of the acid.
3. Fill cells to the maximum with water.
4. Replace caps. Put into storage.
5. When the battery is needed, empty out the water.
6. Fill the cells with the acid that you stored separately.
7. Charge the battery.
The battery will accept charge and give virtually 100% of the capacity that it had on the day when you put it in storage. The plates will not be sulfated. The plates will not be buckled. I presume this method can preserve lead-acid batteries in storage for decades.

On August 21, 2012 at 2:19pm
Kevin wrote:

I have lead acid batteries that I use on different instruments. Initially they work fine; However, when they deplete they fail to recharge again. The batteries were inspected and they do not suffer from sulfation. The batteries were stored for 4-5 months in room temperatures. What would the problem be?

On August 21, 2012 at 2:48pm
John Fetter wrote:

Kevin - You appear to be saying that your batteries were not fully charged when you stored them. Modern lead-calcium alloy grid batteries can develop what is known in the trade as “open circuit” when left like this. Without knowing what type of lead-acid technology, I am guessing. Might be possible to correct.

On November 1, 2012 at 12:15pm
Judy wrote:

I was told that an easy way to keep seldom used D batteries in a 2 cell flashlight from discharging over time was to put the end one in backwards, so that the batteries negative ends are together instead of positive to negative.  Good advice?

On November 1, 2012 at 4:09pm
John Fetter wrote:

Judy - It makes no sense to connect them back to back. I made a suggestion on Jan 12 - simply put them in the fridge. Low temperature reduces the rate of chemical reactions inside the batteries, hence reduces self discharge.
On another subject. If you want to keep a tube of superglue fresh, put it in the fridge.
It is amazing how useful fridges can be.

On November 3, 2012 at 2:19pm
Judy wrote:

Thanks for the fridge suggestion, John. but I think the idea about connecting them back to back is that both batteries would be in the flashlight.  The fridge is no doubt a good idea for a flashlight in the house but what about a flashlight kept in the car, the boat, and in other places where the fridge isn’t handy. And my main concern is, first, will connecting them back to back actually reduce self discharge and secondly, is it safe?  Does back to back connection increase or decrease the chance of corrosion…or is there no effect at all?

On November 3, 2012 at 5:38pm
John Fetter wrote:

Judy - When flashlights are in the car, the boat and in other places and are not being used, I would naturally expect they would be switched off. Off is off. So why mess with the batteries? Someone else wants to use the flashlight in an emergency - not unusual - and finds it does not work. There is no technical, no practical merit.

On November 7, 2012 at 10:28am
Judy wrote:

Does the back to back connection of the batteries decrease either the self-discharge or the chance of corrosion?  That;s the issue in my question. Is anyone able to address this question?

On November 7, 2012 at 12:47pm
John Fetter wrote:

Judy - It has no effect. Zero. It is a complete waste of time and effort. Probably started as one of those urban legends.

On November 18, 2012 at 4:22pm
Craig wrote:

We live in a very cold winter climate and remove 12v deep cycle batt’s from boats/campers and store in garage until spring (6 mos). How should batt’s be stored and maintained? Should batt’s be stored fully charged? Should a low amp batt charger be used to maintain a constant state?

On November 18, 2012 at 5:31pm
John Fetter wrote:

Craig - ALWAYS store lead-acid at full state of charge. They do not mind the cold although do not let them go much below -10 degrees F. A CHARGED lead-acid battery will not freeze at -40 but will freeze below that. A partially charged battery might freeze at -40. The cold reduces self discharge, prolongs battery life. A low amp charger will keep the batteries fresh. Might be a good idea to use a timer to switch the charger on 30 minutes per day only, to make sure there is no water loss.

On November 18, 2012 at 5:56pm
Craig wrote:

Thanks John. Any worries with gas vapors from charging batteries in the garage?

On November 18, 2012 at 10:52pm
John Fetter wrote:

Craig - None. You would hardly be charging the battery - merely keeping it in good condition.

On December 15, 2012 at 6:44am
Karan wrote:

Thanks for the info.
I am using my laptop battery from last one year. But now i started using laptop like desktop.So is it beneficial to store battery now.?

On January 4, 2013 at 1:17pm
T. Harrison wrote:

I have dozens of cr2032 3-volt lithium batteroes used in votive lights at Christmas. Now I want to store them until I want to use them again. How do I safely store these batteries?
Can they stack? Should there be paper between them? Should they go in the fridge in a sealed plastic bag? Should they not touch each other?

On April 16, 2013 at 12:35am
Freddie wrote:

Whats the best way for getting as much health out of your battery: Using the computer at 100% or disconnecting it and using a cycle?

On August 3, 2013 at 2:50pm
Nader Bourham wrote:

Does putting batteries in a calculator and not using it waste battery?

On August 24, 2013 at 9:15am
Stanley Kaplan wrote:

Best way to vharge NiCad batteries fir battery oowered tools and best way to charge Litham Ion for same tools Also, best way to store the above for severa months ;lrior tous ans store again Thenk You.

On October 3, 2013 at 12:24am
Maria wrote:

Hello,

I want to know what is the ideal Temperature for Li-Ion Batteries transportation (by plane)

On October 3, 2013 at 9:35am
Stanley Kaplan wrote:

Can you please tel me what the best procedure is to charge an 18 volt NiCad power tool
Battery so as not to retain a memory and have the longest life. I use the battery for about on and off at one lalf hour and then charge. I have been told to take the battery , use it regardless of no particular time and when it just about the time when the drill slows down, charge it with the factory battery charger.  ?  Thank you.

On October 5, 2013 at 12:37am
Dinh wrote:

What happen if we store a Lead acid battery which not yet filled acid for a long time?

On October 5, 2013 at 3:31am
John Fetter wrote:

Dinh - I assume you mean lead-acid that has come off the assembly line, never been filled with acid, also known as unformed. I recently used batteries that came off the assembly line in 2002, were kept in storage all this time, filled them, formed them and they worked just fine.

On October 8, 2013 at 3:38am
Dinh wrote:

Thanks Jonh. But I think that is impossible for using a battery stored in 10 years. Did you mean 2002 or 2012? Now I have problem with some batteries produced in 2008 and can not use. I’m trying to know what happened with the plates and the separators.

Thanks for your reply.

On October 11, 2013 at 2:36am
Rolv wrote:

We use Leica Li-Ion battery GEB221 7,4V 4,4Ah
Up till today batteriers were always put in the charger after use and remained there till next time (trickle charger from Leica).For some reason it has deen decided to keep the batteries out of the charger after and between use (some will put a battery showing low capacity into the charger after use and remove when fully charged).
The question is how to ensure that going for work with our total station and always pick a battery with 90%-100% capacity.
Or put it in another way. How much does a battery of this type self-discharge epr week?

On October 13, 2013 at 10:20pm
Matt R wrote:

Rolv, the best way to gauge self discharge is to monitor the battery.  If the cells are unprotected they will never undergo a self discharge.  Most of the time, if not all of the time the circuit board that prevents the battery from going into an unsafe overdischarge varies on the make and model.

I’ve seen some that will never lose a drop after a year while I’ve seen many that’ll go to 0% in a week.

On November 14, 2013 at 4:29pm
gav wrote:

does it effect a car battery if it is store on conrete more so than wood

On November 14, 2013 at 4:58pm
John Fetter wrote:

gav - Absolutely not. There are many lead-acid battery myths and this is one of the silliest.

On November 24, 2013 at 1:40pm
Jacques Charpié wrote:

I have an Bionx electric bike with a Li-Mn battery.

Is it a problem to let this kind of battery on the cold at the office (maybe 0°C, -10°C or lower) during a couple of hours every day? Show I remove the battery and put it inside everyday?

The battery is never at let at low capacity

Thank you

On January 20, 2014 at 10:46am
Judith wrote:

I just watched this video and it is an eye opener about storing batteries.

http://thehomesteadsurvival.com/house-fire-battery-storage-share-video/?utm_source=feedburner&utm_medium=email&utm_campaign=Feed:+HomesteadSurvival+(Homestead+Survival)

On January 28, 2014 at 10:54pm
konings wrote:

can you store lead-acid 2V deep cycle (OPzS) batteries in sea containers (ambient temperature above 40 degr C)? The batteries are new and pre-charged.

On January 30, 2014 at 1:55am
John Fetter wrote:

konings - Bad idea. Too hot.

On January 30, 2014 at 4:48am
konings wrote:

Hi John, that’s what I thought. If the batteries have been stored for 5-6 months in those conditions and after filling with acid the SG level is low (1,160 -1,190) and V between 1.82 and 1.94V - would it be possible to recover them?

On March 14, 2014 at 8:59pm
Gary wrote:

I have an AAS in power generation, and I graduated with a 3.93 GPA and this garble is down right confusing. What say you compile one easy to understand section, instead of letting anyone who thinks they know it all to verbally puke on your site. Don’t get me wrong, many of these people may really know whats up, but who has time to read all this crap, then do research to see what is correct and what is truly crap? Too much, yet too little!