# Tag Info

Accepted

### What causes rechargeable batteries to age? What can be done to extend life of these batteries?

One of the problems that plagued older rechargeable batteries (e.g. Nickel Cadmium ($\text{NiCad}$) and Nickel Metal Hydride ($\text{NiMH}$)) was the memory effect. The memory effect occurs when a ...
• 2,485

### In the Apollo 13 mission, how could the batteries have "no Volts" with two Amps of current?

The part of the movie transcript you're talking about (taken from here) is where Fred Halse says: Batt B, no volts, amps are okay. Batt C, s***. No volts, only two amps. They may die before the ...
• 1,264

### How is it possible that "fiddling around with" batteries can apparently give them more power?

It is common for both the button contacts on the ends of a battery and the springy metal fingers that make contact with those buttons to get a thin film of oxide forming on them. It does not take much ...
• 11.7k

### Why is electrical energy most commonly stored in metal acid batteries?

Using hydrogen efficiently is difficult. If you burn it, you're typically back to IC engine efficiencies, i.e. catastrophically low. If you use it in a fuel cell, that usually involves rare metal ...
• 1,570

### Why aren't gravity batteries everywhere?

So, this battery costs US\$70, weighs 406 grams, and holds around 200,000 Joules of energy. To get the same energy from that weight as a "gravity battery" you'd have to pick it up over 49 kilometers ...
• 2,208

each electrochemical reaction involving a lead atom in a lead-acid cell releases two electrons into the external circuit, which means it has a relatively good extractable power-to battery mass ratio. ...
• 11.7k

### Why aren't gravity batteries everywhere?

Consider 1 kWh = 1000 W * 3600 seconds = 3,600,000 J. 1 kg lifted 1 m = ~10J. Let's use 1 metric tonne. 1000Kg. So we get 10,000 J per meter of elevation. 3,600,000 / 10,000 = 360 meters. Around ...

### Charging a smartphone battery while using it

First of all it is highly unlikely that the one would find public information of major OEM cell phone manufactures battery charging methodology back by technical source and citations as this would be ...
• 7,103

### Charging a smartphone battery while using it

I am not familiar enough with your tests and your data to draw any conclusions from it. Perhaps if you infer your own conclusions citing specific parts of your data I would be able to follow better ...
• 7,444
Accepted

### What are the consequencies of intermittently charging a smartphone battery?

The slower you charge a Lithium battery the better. They are not keen on very fast charge/discharge fluctuations. One reason is that faster charging also results in higher temperatures which stresses ...
• 56

### What are the consequencies of intermittently charging a smartphone battery?

I don't believe periodic charging would damage a smartphone, however it likely wouldn't charge it much either. A typical phone charger today outputs 1 Ampere of current at 5 Volts, and takes perhaps 2-...
• 331
Accepted

### Looking for a device that breaks the circuit if the voltage gets too low

The simple answer is that you can get off the shelf modules which does exactly what you want. They are often called 'split charge modules' and are designed for installations like boats and motor-...
• 15k

### Specific energy vs Specific power in batteries

Batteries can't deliver unlimited current. Internal resistance, and limitations of the chemical reaction within the battery make that it can only deliver so much current. And the more current is drawn,...
• 1,164

### What is the best practice for ensuring the best possible connection between a battery cable and a battery terminal

We really need more info on the batteries and type of connection. Will the connection be permanent? In that case soldering or welding are the best choices. If you're connecting to wire, you'll need ...
• 1,418

### Can lithium ion batteries solve the world's energy storage problem?

I would like to answer this question slightly differently. The challenge with rechargeable batteries (Lithium Ion), each charge discharge cycle causes internal resistance of the battery to increase. ...
• 7,103

### Why is electrical energy most commonly stored in metal acid batteries?

Cost per watt-hour of storage. Other means are either more expensive to manufacture, more expensive to maintain, or have shorter total lifetime increasing the amortization costs. The one viable ...
• 6,113

### Why is electrical energy most commonly stored in metal acid batteries?

One of the reasons why hydrogen isn't more widely used is that is extremely explosive requires great care when bein handled. It also needs to be stored away from naked flames or sparks. The hydrogen ...
• 9,382

### Do commercial fuel cells actually exist or it is just hype?

Fuel cells have hit the start of commercial success in Japan, where sales so far have been at least 120,000. Given they only became viable commercial products very recently, that's pretty good uptake. ...
• 3,681

### Why do rechargeable Lithium Ion & Lithium Polymer batteries explode or catch fire?

Here is a good resource that has very detailed information about Li-Ion hazards: Lithium-Ion Batteries Hazard and Use Assessment (Lithium-Ion Batteries Hazard and Use Assessment. Celina Mikolajczak, ...
• 1,835
Accepted

### What is the capacity of a WWII Submarine battery in kWh?

Collecting bits from sites, fleetsubmarines World War II American fleet submarines had two batteries, each composed of 126 cells. By comparison, a 12-volt car battery contains only 6 cells, ...
• 3,979

### Why Sony headset's charging station doesn't charge other NiMH batteries rather than which came with it?

Looking at photos of the battery used in your headphones, I believe they use one of two ways to do this: 1- The cells are parallel in orientation, leading me to believe they are electrically parallel. ...

### Why Sony headset's charging station doesn't charge other NiMH batteries rather than which came with it?

Based on the information shared and available there mostly three more possibilities. There is a make break switch that is triggered based on the battery packaging. Review the original battery package ...
• 7,103

### Why do modern diesel electric submarines predominantly use lead acid batteries?

Lead-acid batteries are reliable, robust, easily recharged, and exhibit almost zero fire risk. Mass on a submarine is pretty much irrelevant.
• 3,979

### Why do modern diesel electric submarines predominantly use lead acid batteries?

A) Specific energy isn’t so important for submarine batteries since ballast is needed Counter: This doesn’t account for space, which is vitally important, and lead acid batteries have relatively poor ...
• 2,257
Accepted

### How much force needs to be applied on a battery cell to maintain contact?

Here are some examples from Lee Spring that could be useful. All the AA size springs listed have 1.75 lb nominal load. Source: https://www.leespring.com/battery-springs
• 1,367

### Why do I not get zapped when I hold my fingers on each end of an AA battery, like 3R12 ones?

with dry fingers, your skin represents a high resistance to the flow of electricity and so very little of it flows along your skin. In addition, there are no nerve endings right at the surface of the ...
• 11.7k

### What is the minimum current required to charge a smartphone battery?

My input current is 300 milliamps and I am not sure if that will be enough to charge my phone's battery.* It will probably charge acceptably. This varies with product but in most cases modern ...
• 3,824
Accepted

### How to prevent shorts between exposed battery terminals and racing vehicle chassis

1st suggestion would be to find a sturdier cover for the battery. However, it sounds like it might just be badly positioned. Can you move it, rotate it, flip it (if it's an AGM type that will work at ...
• 136