LG HG2 life expectancy

Hi all,

First time posting - long time reading...

We have a battery pack that is 14s7p (52V21Ah) with LG HG2 cells..

Average discharge is about 42A so about 6A per cell..

Without doing the experiments myself I want to try and figure out ROUGHLY how many cycles I can get out this pack and what the degradation in total capacity looks like over the cycles (e.g. every 50-100 cycles)

If we assume I discharge to 70% DOD and discharge at 2C and charge at 0.5C

Anyone here got any data or links to someone else's data? or rough estimation from experience.. I'm interested in data from 0-1000 cycles or beyond if possible

If nothing for LG HG2 then how about Samsung 30Q?

Thank you greatly in advance

In theory, lab conditions, 150-250 cycles at best befor dropping capacity past SoH ~75%.

But in real life, too many variables to be able to even ballpark.

Stopping discharge at a higher SoC and charging at a lower one,

gentle C-rates in and out,

storing at lower SoC and temperatures

are all critical to extending cycle counts.

Expert forum members have not included much about longevity in their test protocols, so basically need to rely on vendor lab specs and member anecdotes.

When you learn more from your own experience, please report back here.

30Qs have a bad habit of dying young, according to feedback I've seen. They get rather hot under normal use, and 300 cycles would be good going.

sandcrabsteve said:

Hi all,

Without doing the experiments myself I want to try and figure out ROUGHLY how many cycles I can get out this pack and what the degradation in total capacity looks like over the cycles (e.g. every 50-100 cycles)

If we assume I discharge to 70% DOD and discharge at 2C and charge at 0.5C

Anyone here got any data or links to someone else's data? or rough estimation from experience.. I'm interested in data from 0-1000 cycles or beyond if possible

If nothing for LG HG2 then how about Samsung 30Q?

Thank you greatly in advance

Click to expand...

there are two known issues with LG HG2:

1) Market is overflooded with LG HG2 fake copies.
2) Original HG2 cell suffers with signifiant capacity drop in the first ca 100 full cycles (at higher DoD no matter on load) This behaviour leads to prefer competitive cells like 30Q or VTC6 by some manufacturers in specific applications. LG HG2 cycle life outperform them both after few hundred of cycles.

Test results:
LG HG2: charge-discharge rate at 100% DoD (4.2V charge with 100mA cut-off, discharge to 2.5V, rest time 10min)
0.5C-1C test: 94% after 50cycles, 92% after 100 cycles, 80% of initial capacity after 1000 cycles,
0.5C-3C test: 90% after 50cycles, 88% after 100 cycles, 79% of initial capacity after 1000 cycles,

LG HG2: charge-discharge rate at ca 85% DoD (4.2V charge with 100mA cut-off, discharge to 3.2V)
0.5C-1C test: 83% after 1000cycles, 77% of initial capacity after 2500 cycles,

Pajda said:

Test results:
LG HG2: charge-discharge rate at 100% DoD (4.2V charge with 100mA cut-off, discharge to 2.5V, rest time 10min)
0.5C-1C test: 94% after 50cycles, 92% after 100 cycles, 80% of initial capacity after 1000 cycles,
0.5C-3C test: 90% after 50cycles, 88% after 100 cycles, 79% of initial capacity after 1000 cycles,

LG HG2: charge-discharge rate at ca 85% DoD (4.2V charge with 100mA cut-off, discharge to 3.2V)
0.5C-1C test: 83% after 1000cycles, 77% of initial capacity after 2500 cycles,

Click to expand...

This is great, thank you!
Is this your personal testing results?

When it comes to LG questions , Pajda is the man .

Pajda said:

Test results:
LG HG2: charge-discharge rate at 100% DoD (4.2V charge with 100mA cut-off, discharge to 2.5V, rest time 10min)
0.5C-1C test: 94% after 50cycles, 92% after 100 cycles, 80% of initial capacity after 1000 cycles,
0.5C-3C test: 90% after 50cycles, 88% after 100 cycles, 79% of initial capacity after 1000 cycles,

LG HG2: charge-discharge rate at ca 85% DoD (4.2V charge with 100mA cut-off, discharge to 3.2V)
0.5C-1C test: 83% after 1000cycles, 77% of initial capacity after 2500 cycles,

Click to expand...

What is that in amps? The C-rating system isn't the easiest to understand at the best of times

Just take the mAh capacity, and multiply by the C-rate ratio.

say 3300mAh capacity, 0.5C is 1650mA current