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Why Lead Nanocarbon Batteries Beat Lithium.

In many ways it seems Lead Nanocarbon is Lithium’s ugly but smarter sister. Lithium is in the media a lot, it’s the sexy technology behind the Tesla Powerwall and electric vehicles. It’s associated with Elon Musk, the leading entrepreneur of Silicon Valley and larger than life personality behind Iron Man.

Lithium has many advantages - a fast charge/discharge rate and a lighter weight (hence its use in electric vehicles), nothing competes with it in terms of energy storage per kg. But for home use, the weight is meaningless.

Lead Nanocarbon, Pb-C or Lead Carbon you hardly ever hear about. Manufacturers like boring Narada spend nothing on wooing the media. The heavyness of the lead makes it unsuitable for vehicles. Just one 6V battery weighs 60kog. Yet for domestic situations it is Numero Uno

It is difficult to compare apples for apples in this area, probably that is deliberate because warranty terms on Lithium batteries don’t hold up to scrutiny very well; I will take arguably the most popular battery on the market today, the LG Chem Resu 6.4 and break down the warranty into bite size chunks.

It says in the sales literature 6000 cycles at 90% DOD which sounds impressive but when you look at the warranty, you see they only allow for 16.1 mWh of capacity.

6.5KW x 90% = 5.85 x 6000 cycles = 35,100 mWh . There is a disconnect between this and what you are actually covered for - the boast is double the reality. If you do the calculations it is really 3,100 cycles at 80% DOD. LG is counting on people being too lazy to count and being pretty successful  by the look of things.

In terms of price, an LG 6.4 is about the same as 14.4KW of Nanocarbons. So in pure KW terms you get more than double the storage for the same price.  To work out bang for buck, lets compare the two at both 80% and 50% DOD for their warranties as these are the most common levels :

14.4KW X 80% DOD = 11.52KW X 2400 cycles = 27 mWh for Nanocarbons vs. 16.1 mWh for LG.

14.4KW x 50% DOD = 7.2KW X 3600 cycles = 25.9 mWh for Nanocarbons vs.  16.1 mWh for LG

Nanocarbons thus are ahead by a long way in terms of value and capacity.

In addition, they are safer for home use as Lithium can be explosive if it becomes overheated eg. a house fire. Also, Nanocarbons work over a much wider temperature range; and their charge/discharge rate is much higher.

Lastly you get degradation with Lithium over time, whether you use them or not, while Nanocarbons only degrade if they are fully charged and not being used. It is possible to get a good 14 years of service out of the Nanocarbons, if you are discharging only down to 50% DOD, while there is no Lithium battery out there than can do that.

February 20th 2017