T-Pain Is On A Boat: [Electric Boats] RE: RE: Hello group

Wednesday, November 13, 2013

[Electric Boats] RE: RE: Hello group

Before we can have a meaningful discussion about lithium cells and their safety and usage, we need to be very specific about the particular chemistry involved charging

The great majority of lithium-ion cell info available on-line (including the one mentioned previously) primarily relate to lithium-cobalt and lithium-poly cells, which are the most used (phones, computers, etc). These cells perform very differently than lithium-manganese and lithium iron phosphate.

I wouldn't consider having a lithium-cobalt or lithium-poly battery bank on board, regardless of the superior performance potential. Those chemistries are simply too risky for me. I have no reservations about lithium iron phosphate.

-Tom

---In electricboats@yahoogroups.com, <white74@...> wrote:

http://batteryuniversity.com/learn/article/lithium_ion_safety_concerns

---In electricboats@yahoogroups.com, <white74@...> wrote:

my intention was not to discuss Li cells but to compare two different manufacturers of NiMH cells
ie sanyo as used in the focus battery pack as opposed to the tenergy ones at 10 AH
I do not claim to know much regarding lithium cell
I do know that corrosion can cause terminals to short out causing rapid discharge
I will defer my opinion to Bob who apparently is more experienced / qualified than I am

---In electricboats@yahoogroups.com, <robert-lemke@...> wrote:

Don't tell the Navy SEALS that will deploy in one of these http://www.militaryaerospace.com/articles/2013/09/combat-submarine-batteries.html or myself and many others on the Cruiser's forum that have embraced LiFePO4 cells for marine use. http://www.cruisersforum.com/forums/f14/lifepo4-batteries-discussion-thread-for-those-using-them-as-house-banks-65069.html

Our hope on this group is to share marine electric propulsion and prefer experience and facts over hearsay.

Bob

From: "white74@..." <white74@...>
To: electricboats@yahoogroups.com
Sent: Wednesday, November 13, 2013 6:32 PM
Subject: [Electric Boats] RE: Hello group

The safety claim is based on something a friend of mine who builds underwater communication devices ... he told me that salt water and lithium is a potential for explosion
perhaps this is outdated information

---In electricboats@yahoogroups.com, <robert-lemke@...> wrote:

Off base on the safety claim. Explain why you feel LiFePO4 cells posses a marine safety issue.

Bob

From: "white74@..." <white74@...>
To: electricboats@yahoogroups.com
Sent: Wednesday, November 13, 2013 5:49 PM
Subject: RE: Re: RE: [Electric Boats] RE: Hello group

the original point was tenergy are standard NiMH cells .... Lithium cells have their own set of issues ... not safe for marine being the first priority

---In electricboats@yahoogroups.com, <mark.internet@...> wrote:

I picked up an escape hybrid pack for $350.00 after I had a bad experience with lead acid batteries.
it is 5.5Ah cells, total volts 325. = 1787.5watts i believe.
I guess I paid 195.80 per Kwh.

If you could direct me to your source for .40/ Kwh with BMS, I would be interested.

Mark

From: "boat_works@..." <boat_works@...>
To: electricboats@yahoogroups.com
Sent: Saturday, November 9, 2013 10:38:27 PM
Subject: RE: RE: [Electric Boats] RE: Hello group

Hi Myles,

I'm not sure what "40c/kwh" is, but if it's 40 cents/kWh, then I wish had I that deal instead of the $418/kWh (without BMS) that I paid for my 180Ah CALBs!

-Tom
---In electricboats@yahoogroups.com, <matwete@...> wrote:

"my only question on the ford escape cells is why use sanyo 5.5 ah cells when the tenergey ones are rated at 10 ah?"
Why stop there?
e.g. "why use 10ah Tenergy cells when you can use 17.5ah Enerdel cells"
Or, "why use 17.5ah Enerdel cells when you can buy a 35ah, 48v Enerdel module complete"
Or, "why use any of those cells when you can bet CALB 40ah or 100ah cells"

It's nice that we have lots of options with Lithium these days.
For about 40c/kwh (including BMS), my pack's Enerdel modules have some of the highest quality (and power) cells.
Better still, I don't have to mess with cells since the modules are already configured for 48v at the factory.
Had the deal with these modules not presented itself, I'd have likely gone with 100ah CALB cells.
But then, I don't know anything about these Tenergy or Sanyo cells.
Are folks going with them because of some good price point?

-Myles Twete, Portland