Upgrading to a larger battery. Trade in the new existing battery for a credit or just buy the new one and have two batteries?

[digtigs]

I will be purchasing a new 2020 Giant Explore E+4 that comes with a Giant EnergyPak 400, 36V 11.3Ah Rechargeable Lithium-Ion. I want to upgrade to the 500 watt battery during the purchase. I was told I had two choices. (1) Buy a new 500 watt battery for $550 and keep the existing battery. (2) Trade in the new 400 watt battery towards the 500 watt and receive a $250 credit.

Although a new battery (as such) for $250 seems like a good deal, my question is (especially during the winter months) will I potentially shorten the life of one or both batteries from lack of use? So Questions are:

1. Trade the 400 watt battery in for the 500 watt and save $250 on the price?
2. Spend the $550 on the new 500 watt battery, have two batteries, and rotate them for different bike rides?
3. Will having two batteries extend the life of both batteries because of fewer charge cycles or will they both die at about the same expected time as one?

For now I may only ride the bike 2 or 3 times a month depending on cold and snow conditions until spring.

Larry G.

 

[rich c]

Keep both batteries. Rotate and carry both for long trips.

 

[Handlebars]

I will be purchasing a new 2020 Giant Explore E+4 that comes with a Giant EnergyPak 400, 36V 11.3Ah Rechargeable Lithium-Ion. I want to upgrade to the 500 watt battery during the purchase. I was told I had two choices. (1) Buy a new 500 watt battery for $550 and keep the existing battery. (2) Trade in the new 400 watt battery towards the 500 watt and receive a $250 credit.

Although a new battery (as such) for $250 seems like a good deal, my question is (especially during the winter months) will I potentially shorten the life of one or both batteries from lack of use? So Questions are:

1. Trade the 400 watt battery in for the 500 watt and save $250 on the price?
2. Spend the $550 on the new 500 watt battery, have two batteries, and rotate them for different bike rides?
3. Will having two batteries extend the life of both batteries because of fewer charge cycles or will they both die at about the same expected time as one?

For now I may only ride the bike 2 or 3 times a month depending on cold and snow conditions until spring.

Larry G.

If having 2 batteries, my strategy would be to keep the newer battery at storage charge until you need to start using it because the older battery isn't enough for the daily bike use, or if you need it for some longer trips. I see no gain, only loss of value in rotating 2 batteries if 1 is enough per day. So I would keep it at a nice temperature and at proper storage charge until needed.
My own use is just right for the range for now but I know I'd like to take some longer trips sometimes, so I'm considering a second battery on sale.
This is, of course, just based on my perception of how to get best value in that situation.

 

[harryS]

If you can maIntain both around half charge when you're not riding, there's not much loss in longevity. If you didn't buy the bike, the packs are likely shipped/stored at half charge anyway.

Everytime I've bought a new pack, I check its voltage when it comes in and it's a little below the nominal value, which is about half empty.

 

[Slow Rider]

I have a 2019 Explore E+3 and love it. No problems at all, and it's fun to ride. Hope yours is too!

If you're going on long rides, Rich C's advice is great! But if I had been offered those options when I bought my bike I think I would have only gotten the single 500wh battery. My rides are short enough that I don't need to swap the battery, and also short enough so that I don't run out of juice and have to wait for the battery to recharge before I can go ride again. I'm guestimating that if you ride 25-35 miles a day or less, you might be better off with a single battery. You could then buy a new fresh battery in 3 or 4 years when the 500wh battery has degraded and no longer has the capacity you need.

If you believe Giant's propaganda, their "batteries can comfortably be charged 1000 times up to and including 100% of full capacity". Once you hit the 1000 cycles, Giant starts limiting the max charge, "Reaching 1000 charges isn't a cut off either - the battery will uniquely simply ‘step-down’ to a slightly lower capacity, up to 80% of full capacity for a further 800 charges, then up to 60% of full capacity for 600 charges and so on, so it can continue to be used for a long time." https://www.giant-bicycles.com/gb/news/all-you-need-to-know-about-panasonic-e-bike-batteries/23652.

 

[6zfshdb]

IMO, the answer to your question depends mostly on your budget. If you can afford it, $250 for a new battery is a good price. Even if you don't need a second battery now, your riding habits could change. This may indeed happen when you discover the enjoyment of riding a e-bike. Riding longer and more frequently is a distinct possibility.

If you don't use the battery right away, as others have said, store it at half charge and degradation will be minimal.

In addition to giving you extra range, a second battery can be useful if one should fail. You can continue to ride while you seek a repair or replacement.

A second battery could also extend the useful life of your bike should the manufacturer discontinue that particular type of battery.

 

[Handlebars]

A second battery could also extend the useful life of your bike should the manufacturer discontinue that particular type of battery.

That is a smart point to make regarding bikes that have a proprietary battery.

 

[AHicks]

I think a lot of this answer is going to depend on how frequently you plan on going on trips long enough to where you need 2 batteries. Personally, my butt hurts just thinking about this potential.

The second is, knowing full well a battery that's just sitting unused isn't going to last much longer than one used frequently, I would ask myself if I were going to be riding frequently enough to keep the extra battery in use regularly.

Again personally, I would most likely opt for a single battery big enough where I could get through a day with it. My vote, FWIW.

 

[harryS]

The second is, knowing full well a battery that's just sitting unused isn't going to last much longer than one used frequently, I would ask myself if I were going to be riding frequently enough to keep the extra battery in use regularly.

I have to disagree here. I figure these packs have on/off switches so when they are off, the internal circuitry isn't draining the battery. Then a new battery sitting in inventory should have the same shelf life as the internal cells, which is long.

 

[MikeDD]

I have two batteries for my bike. The original battery was replaced under warranty and I decided to buy another. I can be gone from my home base for more than a month. My bike is part of the enjoyment of my trip. I decided having the second battery would allow me to continue daily riding if one battery should fail.

 

[Slow Rider]

I have to disagree here. I figure these packs have on/off switches so when they are off, the internal circuitry isn't draining the battery. Then a new battery sitting in inventory should have the same shelf life as the internal cells, which is long.

Batteries deteriorate from just sitting, here's an example chart from https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

 

[Browneye]

What makes you think you need the bigger battery in the first place?
I'm getting forty to fifty miles on mostly level 3 and 4.
I'm guessing the additional 100 watts of battery rating might take you another eight or ten miles.

 

[DougC]

I will be purchasing a new 2020 Giant Explore E+4 that comes with a Giant EnergyPak 400, 36V 11.3Ah Rechargeable Lithium-Ion. I want to upgrade to the 500 watt battery during the purchase. I was told I had two choices. (1) Buy a new 500 watt battery for $550 and keep the existing battery. (2) Trade in the new 400 watt battery towards the 500 watt and receive a $250 credit.

Although a new battery (as such) for $250 seems like a good deal, my question is (especially during the winter months) will I potentially shorten the life of one or both batteries from lack of use? So Questions are:

1. Trade the 400 watt battery in for the 500 watt and save $250 on the price?
2. Spend the $550 on the new 500 watt battery, have two batteries, and rotate them for different bike rides?
3. Will having two batteries extend the life of both batteries because of fewer charge cycles or will they both die at about the same expected time as one?

For now I may only ride the bike 2 or 3 times a month depending on cold and snow conditions until spring.

Larry G.

I just read the review for the Giant Explore E + 4 on this site. Looking at the picture of the bike I can see that's a big battery. Looks to be similar size as the battery on my Trek Powerfly FS5. I will not be getting a spare battery for the Powerfly due to the size. Even if I had panniers on the Powerfly I wouldn't put that size battery in there. And the weight of the Giant battery is 7.7lbs? Similar to the weight of the Powerfly battery. Too heavy to be carrying as a spare in my opinion. The battery on my Trek XM700 is smaller and weighs around 5lbs. I do have a spare 500WH battery for that bike and it easily fits in a pannier.

I would do the trade.

As for longevity, I've had both the stock 400WH and the spare 500WH batteries for 3+ years and haven't seen any degradation yet. And I don't ride much in the winter.

 

[Stefan Mikes]

A second battery could also extend the useful life of your bike should the manufacturer discontinue that particular type of battery.

I think that was the most valuable point in the whole discussion. Rotating batteries and carrying a spare on long rides makes sense.

 

[PDoz]

If you don't buy both batteries there will be a warranty issue with the 500 and giant will be unable to supply a replacement for months. More importantly, if you DO buy both, then the 400 will turn out to have been the better choice and you get to ride a lighter bike.

I really shouldn't post on forums until I've had my coffee.....

 

[digtigs]

I appreciate all your comments and they all have validity. Having not owned an e-bike before I have no idea how this will all play out. Will I get excited about it because it is fun and keeps my body moving (I'm 68) and use it a lot because I feel healthier and more limber or will it be just a good idea in my head and find I do not use it. I am hoping to get my wife involved because she loves taking pictures and it looks like there are a lot of nice photo opportunities on the bike trails. My thoughts for the larger battery are that I will probably be the pack horse if we both go on trips. One reason to NOT do a lot of e-bikes trips is we like to take our 48 lb. Collie with us on walks, boating, and on vacations; we would both feel guilty leaving her home. If she will tolerate being in an enclosure while towed behind a bike, then I think we will be biking a lot!

Larry G.

 

[PDoz]

I on vacations; we would both feel guilty leaving her home. If she will tolerate being in an enclosure while towed behind a bike, then I think we will be biking a lot!

Larry G.

That makes justifying 2 batteries much easier!
$250 for the ultimate boat battery! You just need to figure out how to adapt it to fit an electric boat motor......
The dog trailer will make carrying that spare battery easy AND necessary.

 

[Johnny]

Keep both batteries, you can always rotate and use them both when you need but you will not be abe to get another battery for 250.

 

[digtigs]

Through all your input I have made a decision. I called FTH Power in California that repairs e-bike batteries to get their thoughts on the subject. Although they would not let me talk to a technician directly, tried to steer me towards calling Giant directly (which Giant's website states call the dealer) the person gave me their thoughts. That basically a battery has a general life to it, meaning that if the battery is designed for 1000 charges / 5 years that whether you charge it 1000 times in that time frame or 500 times in that time frame, the batteries ability to hold a full charge will diminish; meaning it's not solely based on charge cycles. So where I do not know how much I will use the bike, how far a 500 watt battery will take me for my current style or riding, whether I will be a pack horse, or be pulling a collie, I decided that I will take the credit for trading in the 400 watt for the 500 watt battery (buy more accessories) and see how it all plays out.
Again, thanks for all your timely input! Larry G.

 

[Browneye]

I'm pretty sure that's the shop Sam at Fullerton E-bikes recommends. He says anybody would be nuts to buy another battery - just send yours to them and they'll make it better than new for a lot less.

And yes, Li-ion batteries degrade over time. About 15-20% over four or five years. Go check out the Nissan Leaf forums. Some not-so-happy campers there.