90,000 Watt Daily Build Update

[tboorn]

i know they do drop, but from the graphs that are on the lithium websites, and that have been reposted on SMD, show it to be near linear, so say 14.4v at 100% and maybe .1v drop per 5% battery depletion, until around 20% in which the drop becomes almost exponential in form. unlike batteries which fall drastically as power draw is increased, and more visibly i think (volt meter wise).

this is a good read i had come across about the differences in the efficiency and a little about the charging which is why i ask. it also has the discharge graphs for lead acid and lithium

http://www.powertechsystems.eu/en/technics/lithium-ion-battery-advantages/#!prettyPhoto

a little something from it for those who dont wanna read it.

8/ Peukert’s Losses & Voltage Sag Virtually Non Existant

The discharge curve of lithium batteries (especially relative to lead acid) is essentially flat – meaning that a 20% charged battery will be providing nearly the same output voltage as an 80% charged battery. This prevents any issues caused by the “voltage sag” common to lead acid as they discharge, but does mean that any battery monitor or generator auto-start dependent upon voltage levels will likely not work well at all when monitoring a lithium bank.

On the flip side, once lithium batteries are fully discharged, their voltage takes a nose-dive quickly – which is the BMS role to protect the batteries to absolutely never let this happen. Completely discharging a lithium ion bank, even once, can render your entire pack permanently dead.

Another huge advantage of lithium batteries is that Peukert’s losses are essentially non-existant. This means that Lithium-Ion batteries can deliver their full rated capacity, even at high currents. Whereas lead acid can see as much as a 40% loss of capacity at high loads. In practice, this means that Lithium-Ion battery banks are very well suited to powering high current loads like an air conditioner, a microwave or an induction cooktop.

[knowledge]

great info

[_paralyzed_]

yeah these batteries are the next big thing in audio for sure, just a matter on showing people they actually work just like the cap debate when they were first shown. Not comparing the two theyre apple to oranges, just that people were skeptical even though its science haha.

The only thing i havent seen people explaining yet, is what kind of reading device do you hook up to monitor the battery life. Since weve gotten accustomed to using a volt meter to watch our batteries, if you hook one up to a lithium battery, which puts out almost linear power until 20%-10% remains then drastically drops, you wont be able to monitor battery life because at 100% it may put put a constant 14.4v, and at 30% it will still do the same. Is there something as simple as the volt meter to monitor actual charge percentage of the batteries? Ive read there is i just havent seen any in use.

A lithium charger will show the battery's internal resistance. When the internal resistance begins to rise the battery is near the end of it's life.

Do they have a some sort of protection from being over discharged?

That's a good way to kill a lithium batt.

Yes. They have LVC's. (Low voltage circuits)

[sencheezy]

<blockquote class='ipsBlockquote'data-author="tboorn" data-cid="2942130" data-time="1424382986"><p>i know they do drop, but from the graphs that are on the lithium websites, and that have been reposted on SMD, show it to be near linear, so say 14.4v at 100% and maybe .1v drop per 5% battery depletion, until around 20% in which the drop becomes almost exponential in form. unlike batteries which fall drastically as power draw is increased, and more visibly i think (volt meter wise). this is a good read i had come across about the differences in the efficiency and a little about the charging which is why i ask. it also has the discharge graphs for lead acid and lithium http://www.powertechsystems.eu/en/technics/lithium-ion-battery-advantages/#!prettyPhoto a little something from it for those who dont wanna read it. 8/ Peukerts Losses & Voltage Sag Virtually Non ExistantThe discharge curve of lithium batteries (especially relative to lead acid) is essentially flat meaning that a 20% charged battery will be providing nearly the same output voltage as an 80% charged battery. This prevents any issues caused by the voltage sag common to lead acid as they discharge, but does mean that any battery monitor or generator auto-start dependent upon voltage levels will likely not work well at all when monitoring a lithium bank.On the flip side, once lithium batteries are fully discharged, their voltage takes a nose-dive quickly which is the BMS role to protect the batteries to absolutely never let this happen. Completely discharging a lithium ion bank, even once, can render your entire pack permanently dead.Another huge advantage of lithium batteries is that Great read. The juice box does have internal BMS. The shut off for the juice box is 8v. This means that the amps will go into protect well before damaging the battery. Therefor making it nearly impossible to damage the juice box.

[tboorn]

great info

thanks, im glad this post is staying so constructive so we can all actually learn something haha

[ZAPCO209]

Props for going against the grain sancheezy.

[sencheezy]

Props for going against the grain sancheezy.

thanks a lot Zapco. I love the support. I'll keep going at it. All the support helps.

[rockFord_Expedition]

I know my DeWalt drill has a Lithium battery and I can push a button on the battery itself for it to display the battery percentage so I am sure it can't be too difficult to monitor those batts in a vehicle.

[scooter99]

I thought this was a build log, it's turned into a battery info page. Where are the build pics!?!

[knowledge]

well is a new tech so everyone wanna know about it