The UK is a world leader in reducing the number of laying hens kept in battery units. The global average for laying hens kept in battery cages is 70-80%, the UK average is 66%. The sad truth is that free range eggs are not that much better than battery eggs; many chickens never get to go to the small strip of outdoor space that designates the overcrowded flock as free range. Other practices, such as beak trimming, prevent the hen from fulfilling its nature such as pecking at the ground. Any animal which suffers degenerative muscle diseases from not being allowed to have enough physical exercise, sunlight and fresh air cannot be producing eggs that are adequately nutritious. Moreover, these eggs simply have bad energy, or karma - whatever you want to call it: On some level, spiritual or energetic, they cannot be true creators of vibrant health in the consumers.
The best eggs you can buy in the supermarket (if you're not lucky enough to have access to your own chickens) are those that meet the organic standards of the Soil Association. For a bit more info see below (from www.http://www.soilassociation.org/animalwelfare/chickenandturkeys
What is the difference between organic and free range eggs?
Standards have been set for organic and 'free range' which stipulate among other things flock sizes, stocking densities and how many hens can share a nest. Organic standards always state that hens must have access to outside areas; however they also go further than free range standards in a number of important ways.
One of the ways in which organic standards differ from 'free range' is that organic standards stipulate smaller flock sizes and lower stocking densities (the number of birds per square metre). Smaller flock sizes help to ensure healthier and less stressed birds.
Feather pecking is a particular problem on large units and wherever hens are crowded into small spaces. Birds can be seriously injured and even killed as a result. To prevent this, the majority of 'free-range' hens are beak-trimmed – a mutilation that can be painful and also prevents the hens from expressing their natural behaviour by foraging. This practice is heavily restricted by the Soil Association.
Organic farms certified by the Soil Association have to provide more pop holes (exits from the hen house) than 'free range' farms do, to ensure access to pasture is not restricted. Generally speaking, in larger flocks a smaller proportion of birds go outside.
Be careful about misleading labelling - 'farm fresh' or 'country fresh' does not necessarily mean free range.
What is the difference between Soil Association eggs and other organic eggs?
The main differences occur in the sizes of the flocks and the rotation of the land over which the hens can roam. Hens like to dust-bathe, peck and scratch at the earth. If hens are kept in large numbers, the ground can become bare and can sometimes, after a while, harbour potentially harmful diseases. To prevent the birds becoming ill, the ground needs to be rested. The Soil Association states that the land must be rested for nine months, whereas the basic UK standards state that it only needs two months.
In order to maintain the best possible animal welfare, the Soil Association recommends flock sizes of no more than 500 birds. Where farms can demonstrate high levels of welfare, up to 1,000 meat birds are allowed in a house, or 2,000 for egg laying birds. In contrast, non-Soil Association chickens reared to the current EU rules often live in huge flocks - with as many as 9,000 in a single shed – and are then sold as organic.
In smaller flocks the chickens are truly free range. In larger flocks, chickens are more likely to block the doors and this means that many birds may never go outside. Many experts believe that keeping flock sizes small helps to reduce the risk of serious suffering for chickens, caused in part by the birds getting bored and pecking each other's feathers, causing bleeding and even death.
See here for some rescued battery chickens https://www.youtube.com/watch?v=s462lbbxdOI