Benefits of Battery Pack

[TieNN89]

Hi all,
I'm not understanding and maybe I'm reading too much into this.

I'm trying to work out the benefits of having a Battery Pack like the Cellink Neo.
I know they will prolong the life of the car battery because it's not draining the battery down.

But I've read some people say, you get longer Parking Mode with a Battery Pack. But how can this be?
Most of these battery packs are 6AH meanwhile a small car battery has 40AH and on bigger cars they have even bigger capacity.
Would it not mean that you have a longer duration Parking Mode if it was just connected to the Vehicle Battery?

 

[Nigel]

• You should only ever use half the capacity of the car battery, and use a low voltage cut off to make sure you only use half, car batteries are not designed for deep discharge. A lithium battery can be completely discharged and recharged every time.
• Most people will only charge the car battery to about 80% if using it for parking mode due to the fact that it charges very slowly when nearly full, whereas the LiFePo lithium batteries can be charged flat out to 100%.
• Car batteries are not very efficient when discharged slowly.
• Car batteries don't retain 100% original capacity for long, after a couple of years they may only have 50%, while lithium batteries should be able to maintain over 80% for 10 years. (Although I suspect the Neo is a lot less than that.)

So it is a lot closer than it first appears, and it does depend on the size of your lithium battery pack and if it has an extension or not, but yes, generally the car battery will have higher capacity for the first couple of years use, especially if you have a car with a larger battery, many are 65 or 85Ah.

I think the main reason for using battery packs is that some vehicle manufacturers (mainly german) install systems to monitor battery use and issue warnings or service demands if you plug into the car battery. Potentially this can be expensive and they could try to get out of warranty claims on the basis of unauthorised battery use. So choose your car carefully if you want to use parking mode.

Generally, if your car has an AGM battery, as used for stop-start systems, then you are better off using the car battery, if it has a normal lead acid battery then there is not much in it, except that the battery pack has a significant initial investment while the car battery may need replacing sometime in the future, if you don't sell the car first! Also, car batteries are available at significantly less cost than lithium batteries, but that does depend on where you buy them, a car battery from a german car manufacturer fitted by the dealer is likely significantly more expensive than the lithium battery.

AGM car batteries charge much faster than normal car batteries or lithium batteries, so start discharging from nearly full and can be discharged further without damage, so are a good option, and can be used as replacements for normal car batteries when the normal battery wears out.

 

[Indian]

The AGM batteries in the stop-start systems are only charged up to 80%. This to allow the regenerative brakes to dump the load into the batteries every time you brake. These cars have the smart alternator with the current controlled by the ECU and not a regulator as in the conventional alternators.
I dont think you should start draining these batteries as the are very sensitive to voltage fluctuations.