31

You will often find that batteries will give a last little bit of juice - especially when cold - by gently warming them to body temperature - so pop them inside your clothes for ten minutes or so or rub them briskly between your hands for a short time. Also turn them in place to ensure that the contacts are as clean as possible.


26

You can test if your batteries are dead by dropping them on a hard surface - just 5cm worked for me. If your battery is alive, it will not bounce, and a discharged one will. Why? A non-rechargeable battery begins with zinc powder mixed into a gel containing a manganese dioxide powder. As the battery discharges manganese dioxide powder changes to ...


13

Measuring the voltage with a multimeter gives a perfectly fine indication of charge. You just need to know how to convert the voltage into a useful form. For most 1.5V alkaline batteries, (voltage-1)*300 will give you the approximate percentage remaining. Same formula works for 9V alkalines, only it's voltage-6. Note this is only for alkaline. Other ...


12

I have always just dropped the batteries on the floor to get more juice out of them. I don't know why it works, but I suspect that it has something to do with the fact that the batteries rely on a physical phenomenon (chemical energy) and that a good shock mixes it up enough to get more juice out. Maybe the shock breaks crystals that have formed in the ...


10

Fold a piece of cardboard to the required size, and make sure it is thick enough to put some pressure on the batteries to hold them in place. Then secure the cardboard into position with some cloth tape.


10

A battery, once it starts to expand or leak, cannot be safely "restored". A leaking battery will, at the least, corrode the phone and it also may catch fire. If you cannot change the battery yourself, take it to someone who can.


8

If your device requires at least two batteries oriented in different directions, switch the batteries' positions. This will alternate the direction of current and squeeze a little more juice out of them. Not much, but usually enough for 10-15 minutes, depending on your device. For example, in this unit, move the batteries at positions 1 and 3 (numbering ...


8

Batteries have greater leak risk the more they are discharged. You might do the following: Keep the item in a cool place. If the item has been used much, replace the batteries before storing even if they have charge remaining. Inspect the item at least yearly. Use reputable batteries since cheap batteries have greater long term leak risk. Do not store an ...


8

I cut up an old plastic gift card. Fit it into the space and secured it with paper tape. It works great and holds the batteries in place.


7

A few things I always do to try and preserve my battery life: Reduce Brightness I always have the brightness as low as possible while not having to strain my eyes to see the screen - the dimmer the screen, the less power it uses. Also turn off auto brightness as this usually takes more battery than needed. Turn off WiFi and Bluetooth Always have these off ...


7

Make sure that geolocation, bluetooth and wi-fi, 3G are turned off when not needed - they often consume much power Also, when you don't use or don't need cellular communication, turn it off also (this and above can be turned off by enabling "Airplane mode") Quit all the apps you are not using Remove all the apps you don't need or turn off undeleteable ...


7

I suggest rotating the batteries through the charger. If it takes two hours to get a full charge on two batteries, that would be 120 minutes. Total time to charge 3 batteries would be 50% more than that or 180 minutes. Put batteries in the charger for one-third of the 180 minutes which woulds be 60 minutes. Remove the battery from the left. Move the one from ...


5

For the A-type batteries, drop them with the flat (negative) side down. If they land and "stick" (stay on negative side, they don't fall over), the battery is good. This YouTube video explains this trick much better. For your 9V and CR2032, testing with multimeters is actually pretty accurate. When new, they should be slightly greater than 9 volts and 3 ...


5

My take is that the multiplier in the formula is incorrect. For 1.5 volt alkaline batteries it is (voltage-1)*200. For 9 volt alkaline batteries it is (voltage-6)*33.3. A 1.5V battery is exhausted at 1V and a 9V battery is exhausted at 6V. A 1.5V battery has .5V of life and a 9V battery has 3V of capacity. You need to find the percentage of remaining life ...


5

Replace the batteries at 11:59 PM. By the time they're changed, it will be midnight, which will be the default time on your clock. You won't need to change the time at all!


5

The battery is unrecoverable. It must be disposed of carefully and safely. You can possibly recover the phone. After removing the battery, you must carefully clean away any residue and liquid. Isopropenol can be used for this, or a fibreglass pencil if necessary. Wear gloves, what leaked out might be corrosive. If in doubt, take the phone to a professional ...


4

There's no (known) hack for this -- you should buy a better charger, that can charge any number of batteries at the same time; anything else probably isn't worth the effort, probably isn't safe, and could damage your batteries. See here and here for more info on why this is so. I had this same problem (but with three-cell LED headlamps). Finally gave up ...


4

As it has been stated before without truly reading your request, a specific type of ladder is your best bet along with a "reach tool." The "reach tool" for someone of your height would probably come in handy for many other tasks as well around your house. Depending on where you live, many hardware stores rent ladders for a low couple hour fee. Home Depot ...


4

The reason two cells worked in your scale is that the scale is internally regulated to compensate for voltage drop as the battery runs down. If the scale worked with two of the 2025 cells, there's no reason to expect it'll suddenly stop working or sustain damage -- if that were going to happen, it would have happened either immediately on inserting the ...


3

A quite similar answer has already been posted, but I can't comment yet so here is mine: For AA or AAA alkaline batteries you can slightly deform them by hitting them gently with a hammer. It gives a little extra life. Be cautious to not tear or break the battery, it contains toxic products !


3

Cell phone batteries (and everything else nowadays) uses Lithium Ion batteries. Unlike previous generations, these don't have a "memory" effect, so there's no need to completely discharge them all the way and then recharge them. In fact, frequently adding small amounts of charge (like taking it on and off a wireless charger) is a recommended use case. What ...


3

If it is a delicate connection, I wouldn't ever use sandpaper on it (nor do I think it would help). Connector problems usually fall in two categories: the pins and the jack do not connect properly (for example because of dust), or the the connector(s) have a faulty connection internally. Cleaning the connectors would only solve anything if the problem is ...


3

Replacing one cell at a time doesn't work because, first, a single cell has too low voltage to operate the clock, and second, the cells are in series, so both are required to form a circuit. If you can manage to supply 3V to the terminals in the battery compartment, in a manner that won't be disconnected when you remove the batteries, that will keep the ...


3

To achieve that in electronical way! you can use something called Multiplexer "power mux" this IC works as a switch, it will take voltage from two sources when the main source cut out it will switch so fast to the second source. In your case connect your clock to this circuit, provide a second power source to it, when you take the battery off it will switch ...


3

In this sort of situation, I normally use aluminium foil. It can be folded the required number of times to achieve the 0.7mm that you need. A good tip is to cut a strip of foil, maybe 20cm long and 1cm wide, then fold it until it's a 1cm*1cm square. If it's too thick, unfold, cut some off and re-fold. Having a continuous strip ensures that there is always a ...


2

I touch "+" with tip of my tongue. If battery is dead, it is tasteless, otherwise it's like a lemon. Don't try it with 9 Volts or more - it's painfull. 1.5V is ok.


2

For 9V batteries you may touch the contacts with the tip of your tongue and if you feel a light tingle that means there's still charge left. If you feel nothing, the battery is dead


2

You can partially recharge certain types of non-rechargeable battery by putting them in a battery charger. They don't advise this but I'm not sure whether that is because it will decrease sales of new batteries or because it might be dangerous. I suspect the answer depends on the type. I've certainly done it with the old-syle (zinc-carbon?) batteries. ...


2

tbh the best way to awaken dead batteries is to rub both ends (+ and -) of the batteries vigorously on a cloth material, such as a sofa or an arm chair for about a minute. By rubbing the batteries, static electricity is built up as well as heated up as per @Steve Barnes and can make "dead" batteries last a very long time (up to two weeks of casual use in my ...


2

Take a rechargeable battery out of some other device in the house, and charge it No other rechargeables in the house? Buy or obtain (places like supermarkets have battery bins where old batteries can be put for recycling. Someone is bound to have thrown a rechargeable away by mistake) another battery. If you're good at losing batteries but good at not ...


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