Here's a good one, actual energy density NiMih vs Lithium by volume

[Greg Elmassian]

OK, while answering another post, I gave the "common wisdom" of more energy in a smaller space for lithium battereis.

but then I started researching the differences between Nickel Metal Hydride (low self discharge types) and Lithium Ion (the standard metal cylindrical cells like 16450) which are Lithium Ion Phosphate.

I know the lithium ion cells are lighter, but I wanted the comparison by physical VOLUME.

So far, all I found was the Wikipedia page:

Comparison of commercial battery types - Wikipedia

en.wikipedia.org

So I was surprised to find that the two, according to this page, were basically the SAME in terms of energy per volume.

Look carefully, the column is titled: "Energy Density by Volume"

Also be careful to look at the same batteries:
"low discharge nickel metal hydride" 353 Watt-hours per liter
and
"lithium cobalt oxide" 560 Watt-hours per liter.

(this is one of the typical chemistries for "lithium ion")

Lithium Battery Technologies - Li-Ion and LiFePO4 Battery Pack Systems

Lithium battery pack systems offer distinct advantages over other battery packs with respect to long life and capacity for a continuous source of power.

www.epectec.com

so approximately 1.5 times the energy in the same space.

I thought it would be interesting to actually look this up by VOLUME, since in the end, it is watt-hours that gives you run time... thus removing the different voltages from the equation.

I was guessing the ratio was higher, but here it is in black and white.

Greg

 

[PhilP]

Very interesting..
I tend to use Lithium batteries, where size/space is the issue :
3.7V per cell, equates to three NiMH cells..

This quite often means that I can use a smaller number, of physically larger cells.
Normally, the ampere-hour ratings, are pretty similar.

People often quote the amount of current that a cell can supply. This is normally in relation to the capacity of the cell. Lithium batteries can supply an enormous amount of current, but by careful choice, LSD NiMH can also supply surprising amounts of current.

PhilP

 

[Greg Elmassian]

Yes, agreed, was just focusing on how much energy you get per volume, 1.5 times is the answer. With PWM powering most motors, there are no significant differences between voltages to the motor, although motors themselves are nonlinear, but that is another discussion. (rpm vs voltage)

Greg

 

[Paul M]

The way things are going with batteries and there strengths, soon we won't be building houses with traditional mains wiring, everything will be battery powered and all we'll need is a big charging system

 

[JimmyB]

The way things are going with batteries and there strengths, soon we won't be building houses with traditional mains wiring, everything will be battery powered and all we'll need is a big charging system

A USB socket on the solar panel

 

[maxi-model]

The way things are going with batteries and there strengths, soon we won't be building houses with traditional mains wiring, everything will be battery powered and all we'll need is a big charging system

I have a friend who has lived the past 4 years full time on a 70ft canal "broad" boat. Her boat is noted in that community as being unique in being entirely electrically powered. And all from the solar panels mounted on the roof. OK, the owner uses a wood burner for the heating but all other power use, motors included, is from the onboard batteries. It does not need connection to a canal side power service point, even in the short winter days. Max

 

[Paul M]

I have a friend who has lived the past 4 years full time on a 70ft canal "broad" boat. Her boat is noted in that community as being unique in being entirely electrically powered. And all from the solar panels mounted on the roof. OK, the owner uses a wood burner for the heating but all other power use, motors included, is from the onboard batteries. It does not need connection to a canal side power service point, even in the short winter days. Max

That's good going, No1 Child lives on a smaller boat that she plugs in on a marina, but she needs to be careful on cruise mode, and she has a diesel engine. Using the inverter without the engine running kills the batteries within hours.

 

[dunnyrail]

That's good going, No1 Child lives on a smaller boat that she plugs in on a marina, but she needs to be careful on cruise mode, and she has a diesel engine. Using the inverter without the engine running kills the batteries within hours.

I have a friend who has lived the past 4 years full time on a 70ft canal "broad" boat. Her boat is noted in that community as being unique in being entirely electrically powered. And all from the solar panels mounted on the roof. OK, the owner uses a wood burner for the heating but all other power use, motors included, is from the onboard batteries. It does not need connection to a canal side power service point, even in the short winter days. Max

Interesting, future has got to be that but till someone gets to grips with feed-in tariffs being better and not giving future prices away to China innovation will be suppressed in U.K. both with battery and solar generation for the household. I wonder if Max‘s friend has a Wind Generator as well, you do and have for many years now seen them in Canal boats.

 

[Ralphmp]

Interesting, future has got to be that but till someone gets to grips with feed-in tariffs being better and not giving future prices away to China innovation will be suppressed in U.K. both with battery and solar generation for the household. I wonder if Max‘s friend has a Wind Generator as well, you do and have for many years now seen them in Canal boats.

My wife tells me that we need neither a wind generator nor a hot air heating system as much of the time I provide both! I’m hoping she’s joking …