Quote:
Originally Posted by Visionary
Most people have limited budgets and its a hell of a lot cheaper to run Lead Acid unless of course, your house is a caravan (mobile) then Li-Ion becomes the obvious choice.
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I think that it is not correct. Do you have any
recent sources to back up that claim?
While lead-acid batteries are initially cheaper to buy, you also have to include the battery lifetime and performance. If this is included the Li-ion batteries have overtaken the lead acid batteries a few years ago and their price keeps going down every day as the technology advances.
1. Li-Ion are almost 98% efficient while lead-acid batteries loose almost 15% of power during each charge and also there are significant losses if they get discharged fast.
2. Lead acid batteries cannot be discharged below 60-ish % without a permanent damage to the batteries. So you get only 40% of usable storage capacity which kind-of defeats the whole point of using them as battery storage. Of course deep cycle lead-acid batteries exist but the price is much higher. On the other hand Li-Ions can be discharged down to 20% without any damage, i.e. you get double the storage capacity compared to a total-capacity-equivalent lead-acid battery.
3. Heat - lifetime of lead-acid batteries is significantly affected by heat. Over 40C is definitely a killer for them and we are in Australia. You will be lucky if you get more than few years of life out of them.
4. Cycle life - up to 4000 cycles for Li-ion vs up to 1000 cycles lead-acid. And this is tested under 20-25C ambient temperatures, the real-life performance of lead-acid batteries will be worse in Australian conditions as per my point 3.
Just look at the warranties. Tesla power wall gives 10 year warranty + optional 10 more years. Please find anything similar for the lead acid batteries.
Also to be mentioned is that lead-acid batteries have much higher environmental impact.
Buying lead-acid batteries may save you money in a short term but it is more economical to get Li-ion batteries nowadays. A few years ago it was the other way around but not any more.