Lightweight Batteries

[tjts1]

Originally Posted by ConnClark

Perhaps you need to read this thread or at least look at the picture before thinking about moving a lithium ion pack into your passenger compartment.

Why you shouldn't mess with lithium ion

Somehow I don't think you have a computer handling the charging to do it safely. Keep in mind even with one these things can still go off.

Straight trippin fool. I hope you leave your lap top and cell phone outside the car too.

[ncwa]

I pulled my 36lb lead battery out of my ‘66 Mustang and replaced it with a 16 Ah custom Headway LiFePO4 pack and BMS (total weight of 4 lbs!). This was a great solution but only worked well for about a month. Over time the battery started to loose cranking amps and eventually it would not start the car. At the time I was having a little bit of trouble with my low voltage relay so I might have dropped below the 2V min limit. I have since switched back to lead. However rather than the original 90 Ah battery, I am using a smaller 45 Ah 19 lb battery. This has been working well but I do keep a close eye on its charge. I think this would work for a smaller engine in a warm climate. (As a disclosure, the Ah rating of my battery is not as critical as I also have a 25 amps coming from my DC/DC converter and I can practically start the car with my e-drive if needed)

[oil pan 4]

My lithium battery pack is still working good after about 3 weeks of use.
My battery pack is in the back seat and has a forklift QD so I can pull it on cold nights. Usually when I bring it in I top it off with a lead acid battery charger set for "deep cycle".
On the 2 amp slow charge it never draws power for more than 10 minutes.

One cold morning when I left the battery in the car it didnt want to do an extended cranking cycle on my car to prime the carb bowls. I need to convert to an electric fuel pump so I dont have to use the starter motor to prime the carb.

I am also going to check for voltage drop on the new wiring to include the grounds.

[redpoint5]

I understand that Li batteries can be discharged deeper than lead acid without causing permanent damage. Can this be done on a regular basis, and what depth of discharge can safely and routinely be achieved?

I'm wondering if I could swap my battery for a lithium and run my car in alternator delete mode while charging the battery every night.

What are your thoughts on running a minimal hassle alternator delete? My daily commute is about 15mi round trip, with weekend commutes of 70mi 1 way.

[oil pan 4]

LiFePO4 batteries can be discharged down 80% where deep cycle lead acids like it about 50% deep and lead acid starting batteries can only take about 15% to 20%.

[oil pan 4]

Oh and I plan on using a LiFePO4 battery in my truck now that I have added some more 1990s tech to my suburban.
After installed the gear reduction starter my truck will fire up with my camaros 20 cell LiFePO4 battery.
DIY: BYOB, for more power, a lot less weight - Diesel Place : Chevrolet and GMC Diesel Truck Forums

[MadisonMPG]

Ebay. They are 4x2 and 4x3. 100 or 130 dollars. Look up motorcycle battery A123.

[oil pan 4]

My trucks lead acid starting batteries have gotten surprizingly weak all of a sudden, the LiFePO4 conversion may happen soon than I thought.
At the start of last winter I thought they might have a year left, looks like I was wrong.
For the truck I plan on constructing a 4x13 A123 pack.

[oil pan 4]

Well my batteries were acting a little weak again, tried charging them like I did on the 22nd of feb, but today they wouldn't charge.
LiFePO4 batteries are on order.

[deathtrain]

good luck, report back and take pics.