J F Telstra replaces their back up batteries every 5 years. They are excellent solar storage batteries. They replace them by date and not condition, they are good for around 15 years. These batteries are sold off.

If you got on to Telstra and told them what you want them for, you may have a sympathetic ear.

Lead acid batteries are no good for storage batteries, you need proper deep cycle storage batteries.
Or deep cycle marine batteries.

JF Aus
Well for that sort of use I would think Nickle Iron cells would be just the job.
They last for 30 years, you can replace if needed single cells, you
short circuit them without damage, they can be left for years not used
then put on charge and away they go.
You can recondition them yourself if needed, but I think they are
larger for the same capacity, but for the sort of place you are speaking about they could be ideal.

http://www.ironcorepower.com.au/page3.php

Second last sentence of the article: "We are at the start of a market driven revolution which will sweep all before it, over-riding government ideology and policies."

Rich Americans can preach "freedom" because they can buy it from the front of the queue. But such "freedom" doesn't apply to us mere mortals.

If there is mass use of batteries government POLICIES and regulations will need to be stepped up in such areas as:

- safety standards for battery operations including fire (when charging) especially any dangerous emissions or explosions from burning batteries. This also applies to normal house fires spreading to batteries

- imports of cheap n dangerous batteries from non-US sources (eg. China, Bangladesh, India).

- safe and economic disposal of batteries on a mass basis

- prices charged by older style electicity networks for people who cannot afford solar or batteries

- costs and rights for solar users (semi-free riders) to opt back into electicity networks on a mass basis

- pollution from industries that make batteries and dispose of them?

How rare or plentiful are the chemicals that go into batteries?

Lead batteries. Lead poisoning is already a massive problem.
https://en.wikipedia.org/wiki/Lead_poisoning

Then on top of all that, we will need to train an army of people to
service the battery backup systems.
Just that overhead may well push the system into complete economic failure.

Then there is the real problem. The battery has to be able to store
an unknown number of days of overcast skies and low to nil wind speed.
Just for discussion sake let us say 4 overcast windless days.
The solar/wind system has to have a capacity 5 times a single days
consumption. The batteries have to have capacity to hold 4 days demand
plus enough to get the system up and running for the next sunny day.

That surely makes the whole system impossible financially.
It amounts to a five times increase generation and perhaps a three
times increase in price, assuming some costs are fixed no matter
what the generation capacity.

Again, solar and wind cannot do the job, we need to put more effort
into some other alternative system. We have wasted billions on solar
and wind. They are useful, but are just not what we need.

Then we get seven overcast windless days in a row !

Hi Bazz

In your post of 28 Sep you raise the question of heat generated by rapid battery charging. If we are talking Lithium-ion batteries, that is as good point.

But in the case of graphene batteries it isn’t a problem at all. My understanding is that graphene battery recharge, faster than 15 mins has been achieved with no heat problem.