BU-104a: Comparing the Battery with Other Power Sources

Discover how the battery surpasses other power sources on readiness and efficiency but lacks on longevity and cost.

One hears of wonderful improvements in battery technologies, each offering distinct benefits, but none providing a fully satisfactory solution to all of today’s energy needs. Though the battery has many advantages over other energy sources, it also has major limitations that need addressing.

Energy storage

Batteries store energy reasonably well and for a long time. Primary batteries (non-rechargeable) hold more energy than secondary (rechargeable) the self-discharge is lower. Lead-, nickel- and lithium-based batteries need periodic recharges to compensate for lost energy. (See BU-802b: What does Elevated Self-discharge do?)

Specific energy (capacity)

Compared to fossil fuel, the energy storage capability of the battery is less impressive. The energy by mass of gasoline is over 12,000Wh/kg. In contrast, a modern Li-ion battery only carries about 200Wh/kg; however the battery has the advantage of delivering energy more effectively than a thermal engine. (See BU-1007: Net Calorific Value.)


Batteries have a large advantage over other power sources by being ready to deliver on short notice – think of the quick action of the camera flash! There is no warm-up, as is the case with the internal combustion engine (ICE); battery power flows within a fraction of a second. In comparison, a jet engine takes several seconds to rev up, a fuel cell requires a few minutes to gain power, and the cold steam engine of a locomotive needs hours to build up steam.

Power bandwidth

Most rechargeable batteries have a wide power bandwidth, meaning that they can effectively handle small and large loads, a quality that is shared with the diesel engine. In comparison, the bandwidth of the fuel cell is narrow and works best within a specific load. So does the jet engine, which operates most efficiently at a defined revolution-per-minute (RPM).


The battery runs clean and stays reasonably cool. Most sealed cells have no vents, run quietly and do not vibrate. This is in sharp contrast with the ICE and large fuel cells that require compressors and cooling fans. The ICE also needs air intake and provision to exhaust toxic gases.


The battery is highly efficient. Li-ion has 99 percent charge efficiency, and the discharge loss is small. In comparison, the energy efficiency of the fuel cell is 20 to 60 percent, and the ICE is 25 to 30 percent. At optimal air intake speed and temperature, the GE90-115 on the Boeing 777 jetliner achieves an efficiency of 37 percent. The charge efficiency of a battery is connected with the ability to accept charge. (See BU-808b: What causes Li-ion to die? under Coulombinc Efficiency.)


The sealed battery operates in any position and offers good shock and vibration tolerance. Most ICEs must be positioned in the upright position and mounted on shock-absorbing dampers to reduce vibration. Thermal engines also need an air intake manifold and an exhaust muffler.

Operating cost

Lithium- and nickel-based batteries are best suited for portable devices; lead acid batteries are economical for wheeled mobility and stationary applications. Price and weight make batteries impractical for the electric powertrain in larger vehicles. The cost of drawing energy from a battery is about three times higher than getting it off the AC grid. The calculation includes the cost of the battery, charging it from the grid and budgeting for an eventual replacement. (See BU-1006: Cost of Mobile Power.)


With the exception of watering of flooded lead batteries and exercising NiCds to prevent “memory,” rechargeable batteries are low maintenance. Service includes cleaning the corrosion buildup on the outside terminals and applying periodic performance checks.

Service life

The rechargeable battery has a relatively short service life and ages even if not in use. The 3- to 5-year lifespan is satisfactory for consumer products, but this is not acceptable for larger batteries. Hybrid and electric vehicle batteries are guaranteed for 8–10 years; the fuel cell delivers 2,000–5,000 hours of service, and depending on temperature, large stationary batteries are good for 5–20 years.

Temperature extremes

Like molasses, cold temperatures slow the electrochemical reaction and batteries do not perform well below freezing. The fuel cell shares the same problem, but the internal combustion engine does well once warmed up. Fast charging must always be done above freezing. Operating at a high temperature provides a performance boost, but this causes rapid aging due to added stress. ( See BU0502, Discharging at High and Low Temperatures. )

Charge time

Here, the battery has an undisputed disadvantage. Lithium- and nickel-based systems take 1–3 hours to charge; lead acid typically takes 14 hours. In comparison, filling up a vehicle with fuel takes only a few minutes. Although some electric vehicles can be charged to 80 percent in less than one hour on a high-power outlet, Li-ion batteries get stressed on ultra-fast charges. (See BU-401a: Fast and Ultra-fast Chargers.)


Nickel-cadmium and lead acid batteries contain hazardous material and cannot be disposed of in landfills. Nickel-metal-hydrride and lithium systems are environmentally friendly and can in small quantities be included with regular household items, but authorities recommend that all batteries be recycled. (See BU-705: How to Recycle Batteries.)

Last Updated 2016-07-07

*** Please Read Regarding Comments ***

Comments are intended for "commenting," an open discussion amongst site visitors. Battery University monitors the comments and understands the importance of expressing perspectives and opinions in a shared forum. However, all communication must be done with the use of appropriate language and the avoidance of spam and discrimination.

If you have a suggestion or would like to report an error, please use the "contact us" form or email us at: BatteryU@cadex.com.  We like to hear from you but we cannot answer all inquiries. We recommend posting your question in the comment sections for the Battery University Group (BUG) to share.

Or Jump To A Different Article

Basics You Should Know
The Battery and You
Batteries as Power Source


On August 1, 2011 at 2:59am
hoh wing tuck wrote:

Hi, I manage all the UPS installation across the Asia Pacific region.
I notice we have slightly different voltages for different sites.  The charging voltages range from 13.32 - 13.70 volts [per battery block].  According to some of the UPS manufacturers, the charging voltage should be 13.65 Volts and not lower.
We use mainly Valve Regulated Lead Acid battery for our UPS systems
How can I determine what is the optimum charging voltage for the systems.
What will happen is the charging voltage is too low or too high.  What is too low and too high.

On March 20, 2012 at 5:10pm
Frank Nichols wrote:

Q:  My home security system came with a 12-volt 4ah rated battery ... is there a problem if I use a 12-volt 5ah battery to replace?  Both are sealed acid type batteries.  Thanks.

On October 29, 2012 at 3:21am
alyas wrote:

i have a question about battery element tester
can i now , how work the element tester?
what about riplle and level on the battery element tester?

On February 27, 2013 at 1:55pm
eric wrote:

Hello, I was wondering how many cordless drill batteries are sold in the united states. I am doing a project on cordless drill batteries and needed to know statistics and the market for cordless drill batteries. Thank you

On June 26, 2013 at 8:11pm
Cori wrote:

I am designing a solar panel to charge a 12 volt 6 watt battery that will in turn charge an outsides flow meter. (must be rechargeable)  It will experience freezing temperature to high temperature of 99 Farenhiet. It will experience humidity. It will only have have a few hours to recharge due to optimal sunlight conditions. I want the battery to last a least a year to two years instead of its initial 4 months. The battery will be in constant use. What is the best type of battery for me? I have a decent budget, but it is not that large.

On August 25, 2013 at 9:36pm
Joe Sullivan wrote:

What exactly is “a few percent” when you say “discharge losses are only a few percent”?  And what do you mean by “discharge losses”?  Total capacity of the battery lost by each discharge?  Let’s say a few % is 3%, if you lose 3% of your battery each full discharge, you can only use your battery 33 times?

On February 26, 2014 at 4:59am

I want to charge my solar street light battery of 97.68 AH within 2 - 3 hours - what specifications should the Solar Panel fulfill. The existing Panel is of 12 W and seems insufficient


On March 27, 2014 at 4:10am
Kerry Wagner wrote:

If you lose 3% of your batteries charge capacity at each charging then it retains 97% each charging.  That means if you charge it 10 times it will have 100% of it’s life times 0.97 to the 10th power left.
In an equation this looks like:
What’s Left = (100%) times (0.97 to the nth power)
Where “n” is how many times the battery is charged.
So after 33 charges there is still 36.6% of the battery’s charge capacity left.
The equation in Microsoft Excel is:
where cell A2 has 100 in it and cell B2 has the number of charges the battery has experienced.  The equation above should be in cell C2.
Hope this helps.

On March 27, 2014 at 9:52pm

Dear Kerry,

That you for your explanation.
Basically I require to know if the electrical charge on the Solar panel of a particular capacity say 12 W can have the charge transferred in a faster time to the battery through a booster circuit i.e if the battery requires 6 hours for a full charge - can the charge be boosted to reduce the time to 3 hours



On January 3, 2015 at 7:06pm
Batman wrote:

Can we use the sheer power of will as an energy source instead of batteries?

On June 27, 2015 at 5:18pm
Jake wrote:

I was wondering if you could compare batteries to super-caps too?
I think super-caps are starting to make a splash in the stored power sector.


On July 7, 2015 at 2:04pm
Jeanette wrote:

I am a novice…so please forgive my basic questions!

I am trying to discover what would be best for long term camping.  I have a yurt that is 14’ across that needs a heater using D cell batteries.

I’m wondering about a car battery to run my heater

Would I need an inverter?  ...or some other converter?

Would all this be a good idea?

Thanks for your patience!

On May 31, 2016 at 1:28am
Jie Long Xv wrote:

How about charging through a super capacitor in electric vehicle in the future?
                                ————impression after reading BU104a

On July 5, 2016 at 7:46pm
april wrote:

i am confused.
“Batteries store energy well and for a long time.”
“Compared to fossil fuel, the battery has a low storage capability. “
” store energy well” is contradictory with “low storage capability”, isn’t it?

On August 2, 2016 at 3:21am
Igor wrote:

Just a small comment on ICE engine efficiency.
Contemporary diesel engines and gensets can deliver more than 40% of mechanical efficiency and more than 38% typical electrical efficiency: 5.16 to 5.3 mW of nominal fuel energy (depending on engine and generator model) are converted into 2 mW of electrical energy on generator output. And if you look at big natural gas engines they claim electrical efficiency of 45+ %. With CCHP option total fuel to useful stuff efficiency can be 95% or even more.

On August 17, 2016 at 2:33am
ponmani wrote:

Hi,i am student, what characterization is used to measure the charge and discharge of the battery ,and how to calculate and draw graph for my study

On January 14, 2017 at 3:08pm
Facts are important wrote:

Nice website about batteries and other power sources. I’d like to add my 2 cents worth of color regarding comments about fuel cells.

” the fuel cell delivers 2,000–5,000 hours of service”

There are several kinds of fuel cells, each with different characteristics. The molten carbonate fuel cell has a five year service life or about 40,000 hours. It is used in stationary megawatt power generation applications

Also the molten carbonate fuel cell has a 1200 F operational temperature and is therefore not adversely affected by cold environments. It does take a day to warm up and is suited to provide base load rather than peaking power.

On March 12, 2017 at 11:32pm
Gard Saxon wrote:

Gas stations need to become “cell stops”, where an electric vehicle can quickly be loaded with fresh, recharged batteries and it’s flat batteries removed and recharged. This would also need auto. manufacturers to agree on a standard size and shape for batteries. With the correct automation, this process need take no longer than pumping a tank full of fuel.