Don't charge your bike battery above 80% and don't ride below 20%. Maybe, maybe not.

[Alex M]

I know it was mentioned already, But a good Volt/Ohm meter will give you a Accurate reading, and probably More accurate than your on board display. ?

Yes, but how many people invest $40-50 in a half-decent mutlimeter accurate to (at least) 2 decimal points in 100V range? You want 2 accurate points to make sure that for example, that when it reads 48.12, it is really 48.12 or 48.13 and not 48.19. Most consumers are inexperienced, they are buying $3 Ebay multimeter or same thing from Harbor Freight for $6 and think that it's accurate.

Built-in voltmeter on a charger is more convenient than multimeter, and they are cheap. Ebay is full of $1 panel meters reading 2 decimal points, the 2nd point is rounded up +/- 0.005V, I could live with that, but the readings change if you as much as frown at it. No thermal stability or some other Chinese shortcuts. Tried my luck 2 times, the 2nd time got lucky, works well.

 

[Ian Moone]

Yes, but how many people invest $40-50 in a half-decent mutlimeter accurate to (at least) 2 decimal points in 100V range? You want 2 accurate points to make sure that for example, that when it reads 48.12, it is really 48.12 or 48.13 and not 48.19. Most consumers are inexperienced, they are buying $3 Ebay multimeter or same thing from Harbor Freight for $6 and think that it's accurate.

Built-in voltmeter on a charger is more convenient than multimeter, and they are cheap. Ebay is full of $1 panel meters reading 2 decimal points, the 2nd point is rounded up +/- 0.005V, I could live with that, but the readings change if you as much as frown at it. No thermal stability or some other Chinese shortcuts. Tried my luck 2 times, the 2nd time got lucky, works well.

My point was, IF someone Already had a VOM in their toolbox, then that's an option. Otherwise Walmart has them for Less than $20 ,which is still a good thing to have at your disposal, but Yes voltage sag is no big deal . ?

 

[tomjasz]

I closely follow an electronics channel where lots of cheap electronics get torn apart. components and build quality, as well as accuracy, have been tested on Multimeters in the $10 range. I've been buying these and gifting them. (Link Removed - Attachment No Longer Exists)

 

[Tars Tarkas]

Any opinions on the Luna Advanced chargers?

TT

 

[JRA]

Any opinions on the Luna Advanced chargers?

TT

The 4A one I got from them worked for about 10 cycles and then went to an intermittent phase and now is dead.

 

[tomjasz]

Any opinions on the Luna Advanced chargers?

TT

Save your money, use a cheap fanless until you can budget a Satiator. Ask what the warranty is. I have early versions that all have issues. Chargers have the highest failure rate of any device we buy/use.

 

[Tars Tarkas]

The 4A one I got from them worked for about 10 cycles and then went to an intermittent phase and now is dead.

Did they warranty it?

TT

 

[tomjasz]

Did they warranty it?

TT

There is no warranty coverage. It's decided based on the complaint.

 

[Roxlimn]

I use a Giant pre-built ebike. I charge to about 90+% or 100% whenever I intend to ride the next day, which is nearly everyday. The new charger and battery has a 60% cutoff that I would use if I had to not use the bike for a while. I never use the bike to below 20% capacity since the bundled charge indicator is useless at that point anyway, arbitrarily going to 10 and then 0% suddenly and unpredictably.

For all intents and purposes, I treat 20% as zero percent on both my Giant ebikes.

 

[PaD]

Sometimes when I’ve charged my battery (Vado 5.0 600Wh battery) I notice that charge level increases 2% after charger is disconnected.
I’ve also found that charge level can drop 4% over night. If I return after a ride and battery is 62% I may find that the following day battery is 58%

 

[DDBB]

In summary, everyone should stop obsessing over their batteries but remember; don't charge to 100% and don't discharge below 20%. Store at 40% and avoid heat, cold and don't get the battery wet and don't drop it.

 

[Ian Moone]

I'm sensing a little Battery OCD here ! ??

 

[City Commuter]

I'm sensing a little Battery OCD here ! ??

LMAO!

 

[Mass Deduction]

[...]I find it interesting that there are many posts here about bigger batteries and maximizing range. The 80 - 20 charging "rule" is in direct opposition to these principles. You can't have it both ways.[...]

I don't think those things are necessarily at odds with each other. The larger the battery and the better the bike's range per Wh, the more likely you are to be satisfied with the range you get when keeping the charge between 20% and 80%. In fact, if you're going to do 20/80 charging, that is the best reason to have a large battery IMO. If I was charging to 100% and draining below 20% on a regular basis, then I'd probably be less motivated to pay more for a higher capacity battery. Charging to a max of 80% and not draining below 20% would become a strong motivator to pay more for a bigger battery, at least for me.

Some of the people here are talking about relatively short range on even a full charge. In contrast, a typical Shimano STePS 6100-based city bike with a 504 Wh battery can get about 90 KM on a full charge using high assist, or about 195 KM on low assist (that's advertised range, but I get very close to Shimano's advertised ranges that so they're very reasonable in my experience). So with an old BionX bike I'd almost certainly do a full charge every ride to avoid range anxiety, whereas if I had a brand new long-range Shimano system then I'd almost certainly observe the 20/80 rule because it would be convenient for me to engage in best practices.

For what it's worth, Shimano has chargers that rapidly charge up to 80% and then trickle charge from 80 to 100%. If your battery is dead, it will typically take an OEM Shimano charger about 2.5 hours to get to 80%, and another 2.5 hours to get from 80 to 100%. So Shimano is asserting that being gentle with that top 20% is worthwhile, but their version of being gentle is to charge it slowly rather than to not charge it at all. Food for thought.

 

[DDBB]

It's not a trickle charge after 80%.. The charger switches from constant current and increasing voltage to constant voltage and decreasing current at approx 80%.. All lithium chargers work this way

 

[Toomanycats]

I'm sensing a little Battery OCD here ! ??

When I go out for a ride, it’s strictly recreational, and every ride is Choose Your Own Adventure. I want a fully charged battery so I can ride as far as I want.
I’m saving my pennies. When the battery dies, I’ll get a new battery- or maybe a new bike.

 

[AHicks]

When I go out for a ride, it’s strictly recreational, and every ride is Choose Your Own Adventure. I want a fully charged battery so I can ride as far as I want.
I’m saving my pennies. When the battery dies, I’ll get a new battery- or maybe a new bike.

Me too. I'm just looking for an excuse to replace my 48v with a little higher capacity 52v. Not going to take much.

 

[Solom01]

First world worries. I don't think of myself as an eco Nazi, but I want my batteries to last as long as possible, not because of the cost but because I know that old lithium batteries end up God knows where polluting things to no end. Kind of a by product of our throw it away culture. We can keep talking about how eco friendly ebikes are, but what do you think happens to old lithium batteries?

 

[6zfshdb]

Charging to a max of 80% and not draining below 20% would become a strong motivator to pay more for a bigger battery, at least for me.

I'm sure there are many opinions on this but the motivating factor for me to buy a bigger battery would be simply to get more range. Charge to 100% and run it until the BMS shuts it down. If it means buying a new battery every 3 or 4 years instead of 5 or 6, so be it. Until it fails completely, I compensate for any loss of capacity by carrying a spare.

There will most likely be new battery technology available in the near future and a "dead" battery would be an excellent excuse to take advantage of it. Another factor is the life expectancy of the bike itself. I see no sense in "babying" a battery to make it last beyond the point of obsolescence for either.

 

[DDBB]

The litihium isn't that bad. It's the cobalt