Poor man's Satiator, smart home version

[Bruce Arnold]

Our home was flooded by Hurricane Florence. During the restoration, I decided we'd like having a smart home system. Lights, switches, plugs, fans. It's very convenient and kind of fun. The grandkids love it.

We put a "charging station" in the area where we charge our ebike batteries. Wife has a Pedego City Commuter, I've got a Juiced Bikes CCS. We had the electrician put in a new socket that we use just for our bikes.

Last week, I decided I wanted to make it a smart socket. I got this smart socket and set it up yesterday. We can turn them on/off with Alexa, or put them on a timer through the Kasa app.

We've talked about using the old fashioned timers as the poor man's Satiator. The TP-Link plug cost more, but still not what I'd call expensive, and it fits into our overall smart home scheme.

Right now I've got it on a 5 hour timer. It's a 17.4 Ah battery, it's at about 3/8 charge, and it's a 2 Amp charger, so that's about right. We'll see.

 

[Ravi Kempaiah]

You could go one step further and make it a full fledged "smart home".

My friend did a whole video series on it ...

 

[6zfshdb]

In my case, I have a long obsolete HomeVision computer controller, http://www.csi3.com/homevis2.htm , which has been efficiently controlling my entire home using X-10 modules for over 25 years. I've looked at upgrading to a newer system but the cost is prohibitive. Hey, if it ain't broke, don't fix it.

I have a Grinn Satiator but it only charges one battery at a time. I have 5 batteries which sometimes need to be fully or partially charged at once. I use the HomeVision controller with X-10 modules to power as many as 5 chargers at the same time. Each can be programmed for a specific charge time depending on what % of charge I want. through experimentation, I made a graph comparing charge time with % charge and set the timers accordingly.

Yeah, I've got a lot of time on my hands but I'm a retired electrical engineer and consider this sort of thing a hobby.

 

[ruffruff]

Good idea! I have a couple Kasa plugs to control water pumps for my aquariums.
(I have discus and they require constant water changes!)

I think I'll pick up another and dedicate it to my chargers!

But one thing about this 80% that bugs me??? If you only ever charge to 80% do you ever get to a level where balancing kicks in?
It's my understanding that balalncing takes place at or near a 100% charge?

 

[6zfshdb]

Good idea! I have a couple Kasa plugs to control water pumps for my aquariums.
(I have discus and they require constant water changes!)

I think I'll pick up another and dedicate it to my chargers!

But one thing about this 80% that bugs me??? If you only ever charge to 80% do you ever get to a level where balancing kicks in?
It's my understanding that balalncing takes place at or near a 100% charge?

I think this would depend on your battery BMS. In my case, I always charge to 100% before a ride and then recharge to 80% for storage.

 

[ruffruff]

Ahhh got it! 80% for storage!!!

 

[Alex M]

Common recommendation is 40-60% for storage and 80-100% before use.

With balancing it's more complicated. Most BMS systems won't balance at 80%, but both balanced and unbalanced cells will deteriorate slower at 80% than at 100%.
At the same time, stronger unbalanced cells have to work harder to support the weaker cells. As a result, lifespan of the entire unbalanced battery decreases BUT at the rate different from deterioration due to high voltage.

You don't know how badly they are disbalanced, i.e. how badly you need to balance it, but you do know that cells deteriorate faster if charged 100%.
Some people choose to charge 100% only once in a while, unless they need 100% capacity because their battery is not big enough to support their daily ride when charged 80%.

 

[smorgasbord]

My routine:

• After a ride, clean myself up (to give the battery a chance to cool down), then charge to 80%.
• If I'm going to ride the next day, charge to 90% before going to bed.
• Morning of the ride, charge to 100% while getting ready, etc.
• If I'm leaving first thing in the morning and need the additional range, I'll charge to 100% the night before.

Note that while keeping the battery at 100% for days, especially when hot, isn't good, running the battery down to almost empty also isn't good. I'd rather charge to 90% and end up with at least a bar (or equivalent) remaining at the end of a ride than charge to 80% and have that bar flashing when I get home.

 

[Bruce Arnold]

You could go one step further and make it a full fledged "smart home".

My friend did a whole video series on it ...

I've seen a bunch of that guy's videos. Knowledgeable and a good communicator.

 

[Bruce Arnold]

Good idea! I have a couple Kasa plugs to control water pumps for my aquariums.
(I have discus and they require constant water changes!)

I think I'll pick up another and dedicate it to my chargers!

But one thing about this 80% that bugs me??? If you only ever charge to 80% do you ever get to a level where balancing kicks in?
It's my understanding that balalncing takes place at or near a 100% charge?

I agree. I top them off every so often and leave them on the charger for a while after the light turns green. Having a timer is easier than trying to remember to pull the plug!

 

[Bruce Arnold]

Update: I usually don't ride the bike when voltage gets lower than 46 or so, which is 45% state of charge. Not because of battery longevity; that's just where I notice that performance starts to drop off sharply. I still get noticeable assistance lower than that -- I've never gone lower than 42%, and that only rarely -- but acceleration slows way down.

With my smart plug, when it gets to 46%, if I set the timer on the app to 4.5 hours, it takes it up to just below 52V, which is right around 80%.

The reason I never used one of those cheap timers before is because I'd have to re-set the timer every time I used it, unless I always charged it at the same time. I guess that's doable. Just not the way I operate.

With the smart plug, it's a simple matter to set the countdown timer regardless of when I start charging. And I never leave it on the charger overnight by mistake.

I'm pretty happy with it. My wife likes it too.

 

[teskow]

I normally charge to 80 percent and occasionally to 100 percent. From everything I have read it is the way to do it for battery longevity. Lots of opinions out there to be sure.
I use the timer on my smart phone. I ask Siri to set the timer and unplug when it rings. From 50 percent to 80 percent takes two hours and 15 minutes on my RC. 52v 13ah.