LiGo vs LiGo+ Battery Modules

[Andrew707]

Hello,

Just recently I finished building my first ebike. My goal was to build a simple single speed bike for short (5-10km) commutes around the city.

Here's what parts I've got from Grin:
- Front G311 Motor
- 20A Sinweave Grinfineon Controller
- 2 x 36V LiGo Battery
- T-Lever Throttle
- G311 Torque Arm

So far I'm pretty happy with the setup. The bike is very light - just ~13kg without the batteries. I weigh about 80kg so the torque is good enough to help start pedalling from a stop as well as climbing moderate hills.

I see that Grin released a new model of LiGo batteries called LiGo Plus. In the description, they say

These new LiGo Plus packs are ideal for running ebikes <...> where you want to use just 2 or 3 LiGo modules. They are less stressed and have less voltage sag in these conditions. For large packs (4 or more in parallel) the standard LiGo batteries are still perfectly suited and the most economical.

My questions are:

- Why LiGo Plus is more suitable when using only 2 or 3 modules?

- What might happen if I continue to use only 2 LiGo modules?

- Why is it better to use 4 or more LiGo modules?

- Can I buy an additional one or two LiGo Plus modules and connect them with existing two LiGo modules? Or is it better to keep modules the same?

- So far I charged my two LiGo modules less than 10 times and used them for around 100 km. Two times I discharged them completely but recharged them promptly when I got home. Do you think these modules might still be considered "like new"? Or are they already used and likely hold less capacity so they're not suitable for combining with brand new additional modules?

 

[Taswegian]

• Why LiGo Plus is more suitable when using only 2 or 3 modules?

Different cells inside. LG MG1 vs Samsung 30Q. The latter are rated for higher current.
Fewer modules implies higher current demand per module.
Note that higher current is not universally better, cells are always a compromise between energy capacity, power (current), cycle life, cost, etc etc.

• What might happen if I continue to use only 2 LiGo modules?

Depends how 'hard' you're using them. Pushing the limits of any cell results in energy wasted heating the cell, which has a very negative effect on cycle life.

If you were holding them at 10A discharge for extended periods (ie maxxing out your 20A controller on 2 Ligos) then you should be using the higher rated Ligo+

• Why is it better to use 4 or more LiGo modules?

Parallel more modules to spread the load and lower the current demand on each. Also just carrying more total energy means you're less likely to need to run them from full all the way to empty. Operating 30cells between, say, 90%--30% levels instead of 20 cells between 100%--0% can result on huge improvements in cycle life (like 2 to 3x more).

All this said, one of the big benefits of Ligo is the ability to create nice little minimalist packs like you are doing so I'm not suggesting overloading your lightweight rig. It's just a compromise between using enough modules to comfortably handle the load, or hammer a smaller pack harder and accept it will need replacing much sooner.

• Can I buy an additional one or two LiGo Plus modules and connect them with existing two LiGo modules? Or is it better to keep modules the same?

Talk to Grin.

Normally with batteries you should not mix different stuff. At best the fresher / stronger parts are handicapped by being held back to the level of the weakest link. At worst the weak link is driven to failure which can mean fire.

However...

Grin make great stuff and Ligo apparently have a pretty clever BMS that I believe can talk to other connected modules and act as a swarm. I'm sure Grin anticipated people mashing together modules that might not be at the exact same state of charge or health so probably this is handled well (the video even talks about replacing a single failed module with new)

Talk to Grin

• So far I charged my two LiGo modules less than 10 times and used them for around 100 km. Two times I discharged them completely but recharged them promptly when I got home. Do you think these modules might still be considered "like new"? Or are they already used and likely hold less capacity so they're not suitable for combining with brand new additional modules?

10 cycles aint much, I expect you can treat them as 'new' but you really gotta get your info direct from Grin. If you were to add a third module I would think it should be a regular Ligo to match what you have rather than mix in a Ligo+.

 

[amberwolf]

regarding paralleling modules, there are a lot of threads; not everything in this list is relevant, but you can generally tell by title which are. there are also others that are not in this list, including another ongoing ligo thread.

https://endless-sphere.com/forums/search.php?keywords=batt*+parallel*+-group*+-series&terms=all&author=&sc=1&sf=titleonly&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

 

[john61ct]

The bullet list attribute does not work in all browser/renderers

Here are your questions without those tags

I see that Grin released a new model of LiGo batteries called LiGo Plus. In the description, they say

These new LiGo Plus packs are ideal for running ebikes <...> where you want to use just 2 or 3 LiGo modules. They are less stressed and have less voltage sag in these conditions. For large packs (4 or more in parallel) the standard LiGo batteries are still perfectly suited and the most economical.

My questions are:
Why LiGo Plus is more suitable when using only 2 or 3 modules?
What might happen if I continue to use only 2 LiGo modules?
Why is it better to use 4 or more LiGo modules?
Can I buy an additional one or two LiGo Plus modules and connect them with existing two LiGo modules? Or is it better to keep modules the same?
So far I charged my two LiGo modules less than 10 times and used them for around 100 km. Two times I discharged them completely but recharged them promptly when I got home. Do you think these modules might still be considered "like new"? Or are they already used and likely hold less capacity so they're not suitable for combining with brand new additional modules?

 

[Andrew707]

Talk to Grin.

Normally with batteries you should not mix different stuff. At best the fresher / stronger parts are handicapped by being held back to the level of the weakest link. At worst the weak link is driven to failure which can mean fire.

However...

Grin make great stuff and Ligo apparently have a pretty clever BMS that I believe can talk to other connected modules and act as a swarm. I'm sure Grin anticipated people mashing together modules that might not be at the exact same state of charge or health so probably this is handled well (the video even talks about replacing a single failed module with new)

Thanks for answering my questions. This weekend I went to BC Bike Show and talked to Grin there so they confirmed that it's fine to mix LiGo and Ligo+ modules. So I'll just buy one Ligo+ and it should be all good!

 

[999zip999]

Thanks for getting back with info. Just monitor and keep balance.

 

[zacksc]

Does anyone have an idea what the trade-off is for LiGo+ batteries? For example, do they have fewer cycles than regular LiGo batteries? Do they have a bit less capacity?

The benefit is really clear: more peak current, by the trade-off is not so obvious to me.

 

[goatman]

Does anyone have an idea what the trade-off is for LiGo+ batteries? For example, do they have fewer cycles than regular LiGo batteries? Do they have a bit less capacity?

The benefit is really clear: more peak current, by the trade-off is not so obvious to me.

heres a link to docwares thread showing both these cells

https://endless-sphere.com/forums/viewtopic.php?f=14&t=103092&start=325#p1532787

 

[zacksc]

Does anyone have an idea what the trade-off is for LiGo+ batteries? For example, do they have fewer cycles than regular LiGo batteries? Do they have a bit less capacity?

The benefit is really clear: more peak current, by the trade-off is not so obvious to me.

heres a link to docwares thread showing both these cells

https://endless-sphere.com/forums/viewtopic.php?f=14&t=103092&start=325#p1532787

Wow. Looking at that it seems like the trade-off is pretty clear too. Much more degradation after 700 cycles for the LiGo+ battery (30Q) than the regular LiGo. (Grin calls that cells MG1, and I am associating that with your MJ1. Is that a correct association? )

Comparative analysis:
30Q has a lower internal resistance than MG1.
30Q allows higher current draw.
30Q degrades faster than MG1.

Would anyone like to shed some light on why those things are correlated in that way?

 

[john61ct]

Tweaking chemistries to get higher power output (always afaik) reduces average energy density.

And seems to often shorten lifetime, but I've been told very strongly by people smarter than me, not always the case.

Put another way, if you can afford the weight gain by lowering C-rate requirement by increasing Ah capacity, you get much longer lifespans.

Generally speaking, only go to the high-power density spec you actually need. Better value for money that way too, not just acquisition price but overall cost amortized over years / cycles as well.

 

[goatman]

Does anyone have an idea what the trade-off is for LiGo+ batteries? For example, do they have fewer cycles than regular LiGo batteries? Do they have a bit less capacity?

The benefit is really clear: more peak current, by the trade-off is not so obvious to me.

heres a link to docwares thread showing both these cells

https://endless-sphere.com/forums/viewtopic.php?f=14&t=103092&start=325#p1532787

Wow. Looking at that it seems like the trade-off is pretty clear too. Much more degradation after 700 cycles for the LiGo+ battery (30Q) than the regular LiGo. (Grin calls that cells MG1, and I am associating that with your MJ1. Is that a correct association? )

Comparative analysis:
30Q has a lower internal resistance than MG1.
30Q allows higher current draw.
30Q degrades faster than MG1.

Would anyone like to shed some light on why those things are correlated in that way?

dod is different and discharge amps is different, the 700 cycles was 7 amp discharge. heres a link to how a mg1 does at 2,5,8,10 amp discharge., its just if you lifecycle test a 10 amp cell at 8 or 10 amps it probably wont do as well as the 30q. I think the luna wolf pack offers two different cells for their packs as well depending on the amps you need.

https://electricbike.com/forum/forum/batteries/18650/71533-panasonic-ncr18650pf-vs-lg-mg1-2900mah-10a-cells-discharge-capacity-test