I guess it's nice .... 16 premature deaths of Leaf traction packs ... unless they were one of yours.RegGuheert wrote:Nice find! It's good to see that some used EV batteries finding a second life.....snip.....
I cannot detect any slowing. One owner lost their fourth bar in about the same time as their second (from the previous bar under similar conditions).johnrhansen wrote:Is there an amount of degradation to where the leaf battery pack's loss of capacity levels off somewhat? What would it be?
It depends on the application. For PV, the cycling may limit the further life. But for backup storage, you could perhaps keep it at 50% SOC in an air-conditioned space and get many years of life.johnrhansen wrote:Just trying to find out how long they would last in a stationary application.
johnrhansen wrote:Is there an amount of degradation to where the leaf battery pack's loss of capacity levels off somewhat? What would it be?
A couple of highly coarse data points:RegGuheert wrote:I cannot detect any slowing.
Accelerating? Given that the first CB is a 15% loss and the second is a 6.25% loss, a casual look at your bar loss seems to suggest a slowing trend, not an accelerating one.aqn wrote:A couple of highly coarse data points:
First bar: 16 months/10034 miles
Second bar: 11 months/6479 miles (at 16513 miles)
I hope the accelerating trend does not continue... A casual glance at the "real world losses" tables seems to indicate accelerating timeframe of subsequent bar losses but maybe it was just my skewed perspective.
Agreed. I have concluded that until we get better data from someone with LEAFspy, the best we can do is to look at losses between bars 1 and 2 and between bars 3 and 4, and then only if they occur in the same season. I have only found one such data point::dgpcolorado wrote:I expect it to resume as the weather warms. So, drawing straight lines across seasons isn't useful IME.
Just one data point (since we don't have much data), but it makes it clear that capacity loss does not slow down with degradation. Does it accelerate? It's not clear, but perhaps.As an example, consider member "cyellen" who experienced the loss of bars one and two during the summer of 2012 and bars three and four during the summer of 2013:
Bar 1 to 2: 73 days and 1400 miles
Bar 3 to 4: 64 days and 1500 miles
...Charging to the future
“Affordable and reliable batteries could have a second life in data centres and in the home, starting around 2020,” Nissan’s director for corporate planning, Redmer van der Meer told TechWeek at the launch of GreenDataNet.
Electric cars still have a tiny share of Europe’s car market, but each one holds a battery that can deliver 24kWh of energy. At the end of its life, that battery could be added to a big stack at a data centre, to provide back-up and also power that could smooth the peaks of demand, reducing the data centre’s load on the electric grid.
Van der Meer reckons an electric car will have a lifetime of around 14 years, after which time the battery’s performance will have degraded, but it will still hold around 18kWh. If electric cars take a significant share of Europe’s vehicle market, then there will be a sizeable number of battery modules available – though it will take hundreds of them to power a data centre for any length of time...
edatoakrun wrote:Given the preceding comments, I expect some of you folks are far too full of um...disinformation RE Leaf battery life to accept this, but you just might want to consider the estimate of typical~75% capacity after 14 years (in European climate conditions, and with a typically lower miles driven per year than in the USA, I would expect).