DIY vs a cheap Chins battery

[Jlomb436]

Hello everyone,

I appreciate you taking a look at my post and any input you may have.

In short, I'm aiming to build a "small" DIY solar generator with the goal of making a unit that looks good, is durable and relatively neatly packaged to use a container. This is more of a hobby but would use it for occasional camping/RV trips. In watching Will Prowse's video on Chins, he seems to be impressed by it for it's price point but I find that the casing is quite large for a 100ah battery. Is there any reason I simply couldn't remove it from the case (such as he did in his tear down) and secure it in the DIY case I plan to use for my "generator"? It looks like there is a a few extras inches of foam all around and space will be at a premium.

I had planned to build my own 230ah battery until I saw how compact that Chins was especially with the BMS attached. My calculations show about $0.24 cents for DIY vs $.29 for chins. I may consider buying two, removing them from the package and placing them in parallel. Thoughts?

Thanks all!

 

[HOU_Castle]

Hello everyone,

I appreciate you taking a look at my post and any input you may have.

In short, I'm aiming to build a "small" DIY solar generator with the goal of making a unit that looks good, is durable and relatively neatly packaged to use a container. This is more of a hobby but would use it for occasional camping/RV trips. In watching Will Prowse's video on Chins, he seems to be impressed by it for it's price point but I find that the casing is quite large for a 100ah battery. Is there any reason I simply couldn't remove it from the case (such as he did in his tear down) and secure it in the DIY case I plan to use for my "generator"? It looks like there is a a few extras inches of foam all around and space will be at a premium.

I had planned to build my own 230ah battery until I saw how compact that Chins was especially with the BMS attached. My calculations show about $0.24 cents for DIY vs $.29 for chins. I may consider buying two, removing them from the package and placing them in parallel. Thoughts?

Thanks all!

You will void Chins warranty if you remove them from their cases. Why don't you build your own 230Ah battery (if you feel comfortable building it)? Forum will help you.

 

[Jlomb436]

You will void Chins warranty if you remove them from their cases. Why don't you build your own 230Ah battery (if you feel comfortable building it)? Forum will help you.

Thanks Nola.

I was considering building my own and although I haven't done it before, I'm sure I'd be somewhat competent at it.

So this is my math:
4 x 100ah EVE cells is about $280. BMS is $50-$100. So for 100ah, Chins is ironically the same price or cheaper.
For 230 ah, it's about $650 with BMS I'm guessing.

So it's slightly cheaper on the bigger battery, but for capacity wise, I may just go 100ah to keep this little generator small seeing how I'll onyl have 200 watts of solar for it. If I go smaller, that's why I thought of just unpackaging the chins battery to reduce like 1/3 it's volume. That's sort of my thinking.

 

[HOU_Castle]

Thanks Nola.

I was considering building my own and although I haven't done it before, I'm sure I'd be somewhat competent at it.

So this is my math:
4 x 100ah EVE cells is about $280. BMS is $50-$100. So for 100ah, Chins is ironically the same price or cheaper.
For 230 ah, it's about $650 with BMS I'm guessing.

So it's slightly cheaper on the bigger battery, but for capacity wise, I may just go 100ah to keep this little generator small seeing how I'll onyl have 200 watts of solar for it. If I go smaller, that's why I thought of just unpackaging the chins battery to reduce like 1/3 it's volume. That's sort of my thinking.

If you don't mind of space, you can parallel CHINS batteries to get 200Ah. Chins battery can be paralleled/serried up to 4 batteries according to Chins manual. The positive side building your own battery, you can fix it if there is problem or future expansion and you can make it compact. Either way has its own pros n cons. I have 2 Chins units of 12V-200Ah and one unit Chins 24V-200Ah. They are great batteries. Last time (11/2021), I purchased Chins 12V-200Ah was about $685 (total) via Paypal (not Amazon) with delivery 1 week. Chins battery 12V-200Ah vs 24V-200Ah: dimension wise is exactly the same, the difference is at the weight. 12V-200Ah is 47lbs vs. 24V-200Ah is 96lbs. I built permanent dolly attached to each battery, so they can be portable.

 

[Jlomb436]

If you don't mind of space, you can parallel CHINS batteries to get 200Ah. Chins battery can be paralleled/serried up to 4 batteries according to Chins manual. The positive side building your own battery, you can fix it if there is problem or future expansion and you can make it compact. Either way has its own pros n cons. I have 2 Chins units of 12V-200Ah and one unit Chins 24V-200Ah. They are great batteries. Last time (11/2021), I purchased Chins 12V-200Ah was about $685 (total) via Paypal (not Amazon) with delivery 1 week. Chins battery 12V-200Ah vs 24V-200Ah: dimension wise is exactly the same, the difference is at the weight. 12V-200Ah is 47lbs vs. 24V-200Ah is 96lbs. I built permanent dolly attached to each battery, so they can be portable.

Thanks Nola. Appreciate the insight!

 

[joanna_lannie]

Personally, I recommend DIY batteries, which are cheaper and have a higher degree of freedom. Another point is that because there are so many people in this forum who can help you, you won't get bogged down in the mud.

 

[rruff]

I find that the casing is quite large for a 100ah battery

I ran across this company recently, ToBattery. Since you are undecided on 100 or 200ah they are selling a 150ah battery without a case for $450. They sell on ebay also, with very good reviews (99.7%). They claim low temperature protection as well. Though their warranty terms aren't great (1 year full), I wouldn't expect any of these Chinese companies to honor 5 year warranties.

12V 150AH LiFePO4 Lithium Iron Phosphate Deep Cycle Battery With BMS

Ideal power for Solar Wind RV UPS Audio Marine Kayak.The TOBattery LiFePO4 Battery Model LFP12150BP is a state of the art 12V 150Ah battery.Designed primarily for loads requiring 12V voltages to operate.This battery features a small and compact form factor designed for the smallest fo

tobattery.com

TOBattery 12V 150AH LiFePO4 Lithium Iron Phosphate Deep Cycle Battery With BMS | eBay

TOBattery LFP12150BP 12V 150Ah Lithium Iron Phosphate (LiFePO4) Deep Cycle Battery With BMS. The TOBattery LiFePO4 Battery Model LFP12150BP is a state of the art 12V 150Ah battery. The battery Is made of 4 pcs 150AH Lithium Iron Phosphate Cells.

www.ebay.com

 

[Jlomb436]

I ran across this company recently, ToBattery. Since you are undecided on 100 or 200ah they are selling a 150ah battery without a case for $450. They sell on ebay also, with very good reviews (99.7%). They claim low temperature protection as well. Though their warranty terms aren't great (1 year full), I wouldn't expect any of these Chinese companies to honor 5 year warranties.

12V 150AH LiFePO4 Lithium Iron Phosphate Deep Cycle Battery With BMS

Ideal power for Solar Wind RV UPS Audio Marine Kayak.The TOBattery LiFePO4 Battery Model LFP12150BP is a state of the art 12V 150Ah battery.Designed primarily for loads requiring 12V voltages to operate.This battery features a small and compact form factor designed for the smallest fo

tobattery.com

TOBattery 12V 150AH LiFePO4 Lithium Iron Phosphate Deep Cycle Battery With BMS | eBay

TOBattery LFP12150BP 12V 150Ah Lithium Iron Phosphate (LiFePO4) Deep Cycle Battery With BMS. The TOBattery LiFePO4 Battery Model LFP12150BP is a state of the art 12V 150Ah battery. The battery Is made of 4 pcs 150AH Lithium Iron Phosphate Cells.

www.ebay.com

Thanks man! Pretty cool.

 

[740GLE]

How much for a Chins with Bluetooth BMS to monitor the set up?

DIY with a worth while BMS adds a lot more tweakability, some see huge value in that, some do not.

 

[Jlomb436]

How much for a Chins with Bluetooth BMS to monitor the set up?

DIY with a worth while BMS adds a lot more tweakability, some see huge value in that, some do not.

I was going to skip the bluetooth but thats I think an additional $150 for their smart battery with heaters, I think about $500. My ultimate goal, would to be able to build a relatively flat battery with maybe 4 cells side by side or 2 x 2. It would allow me to keep the form factor small as I'm trying to squeeze in a MPP inverter/charger into a case.

But trying to figure out a way to secure the cells and bus bars for that is daunting at least to me, configurations in general. I'll do some more research as I'm learning. I'm guessing I can just use heavy gauge wire instead of actual bars.

 

[rruff]

DIY with a worth while BMS adds a lot more tweakability, some see huge value in that, some do not.

I thought BMS was more of a safety backup. Charging and discharging parameters can be set with the charge controller. But I guess you could tweak the balancing parameters?

I mostly see value in cells that are matched and will last for 10 years, but that one is tough to pin down... better chances with DIY though.

 

[rruff]

OP, don't know if you saw this thread, but the Chins battery probably has pouch cells: https://diysolarforum.com/threads/new-chins-100ah-lifepo4-battery-teardown.36496/

Actually, any of them might. If you planning to take one apart be sure to check before hand.

 

[rickst29]

I recently completed a "12v" battery, using 230Ah cells from Docan and a high-quality 'Bluetooth-built-in' BMS from JK. I feel that you will "severely" regret purchase of any battery pack with a less capable BMS and no cellphone App capability. High "balancing current" capability is important to keep cells balanced during charging, and to finish balancing them shortly after charging is completed.

For the case of an RV, you might not even need a full 6-sided "battery case". My battery (shown with a previous and somewhat inferior "Daly" BMS) installed to my travel trailer with no case at, firmly held together by the compression plates. On the bottom and partway up the sides, within the RV, there is a motorcycle seat "heater pad" which can be activated by the BMS to warm it up in near-freezing weather, beofre the BMS allows charging to occur.

Depending on your RV install location (and whether you will ever remove the battery from the RV for other uses), you may or may not want a case for insulation purposes. My battery sits within heated interior space, and I don't think that the "heater pad" will ever become activated - except in winter storage, plugged in with a "power converter" responsible for the battery charging process.

 

[rickst29]

I thought BMS was more of a safety backup. Charging and discharging parameters can be set with the charge controller. But I guess you could tweak the balancing parameters?

I mostly see value in cells that are matched and will last for 10 years, but that one is tough to pin down... better chances with DIY though.

A charge controller can merely set voltage for the entire battery pack (4 cells), while a quality BMS will also keep the individual cells in proper voltage balance. In a DIY assembly, you can install a DIY a far better BMS, with much higher balancing current capability - and with cellphone support for monitor/control and parameter tuning as well. I built a larger pack (shown with a previous 'Daly' BMS, later replaced by a superior 'JK' model). In terms of space within the RV, I installed the pack without a case - the "bottom" rests on a BMS-controlled "motorcycle seat" heating pad (which turns on in near-freezing weather, when BMS has disabled "charging" because the temperature is too low). The pad reaches a couple inches up the long side of the "pack", contacting 2 narrows sides of each cell.

The resulting installation is SMALLER than any pre-built "12v" pack of only 100Ah, and the capacity is 230Ah. Why mess with two packs, when you can build greater capacity (than the pair) into a single pack with a superior JK or JDB BMS, pack for roughly the same money?

(Photo is with the older and larger BMS, and the "heater pad" is sitting un-installed on the side. This pack is compressed via springs, a costly and time-consuming "complication" which you might not need. No pre-built battery is compressed in this way.)

 

[Jlomb436]

OP, don't know if you saw this thread, but the Chins battery probably has pouch cells: https://diysolarforum.com/threads/new-chins-100ah-lifepo4-battery-teardown.36496/

Actually, any of them might. If you planning to take one apart be sure to check before hand.

dude, thank you. That would have sucked. I looked around and I think I'm just going to build a 160ah out of cells and a chepa daly BMS. Probably my best bet and I'll get to learn a little bit. Building it is half the fun!

 

[chrisski]

I built my own battery pack. Two batteries 280 ah each.

I saved money compared to buying Battleborns. I did not save money compared to buying the Chins. Chins would have been slightly cheaper. Building the battery took a lot of my time including waiting four months for the cells to get dropped unannounced on my doorstep. And then the building started.

Done again, I'd build it myself.

 

[Alkaline]

Plenty of nice builds diy builds on youtube going over these:

With diy you can fix/replace/upgrade. With Built batteries you are stuck. Chinese Company warranties are worthless most of them will be out of business long before you have issues, the warranty is the 30 days you get from amazon.

 

[Jlomb436]

Plenty of nice builds diy builds on youtube going over these:

With diy you can fix/replace/upgrade. With Built batteries you are stuck. Chinese Company warranties are worthless most of them will be out of business long before you have issues, the warranty is the 30 days you get from amazon.

Thanks man. I've watched a ton of these but I'll check these out as well. My only lack of knowledge I think is BMS and limitations etc. I posted about it here.

These cells with this BMS?

So I don't blow my face off, would these cells and BMS work for my 12v 4 cell battery? That is says 18650 cells is throwing me off. Also, how important is a fan on the BMS? And is Daly's basic BMS version missing a ton of features the ones Will Prowse recommends? It seems to be about 3 x the...

diysolarforum.com

Basically, There is a "cheap" daly BMS for a 12v 4s battery and I think I know what I'm doing but I don't know a basic BMS vs what Will Prowse suggests on his website. I only plan to use a 1200 watt inverter so I'd imagine a 125A would be fine. Additionally, is a fan needed vs passive cooling etc.

 

[Alkaline]

Daly looks beefy ... but acts goofy. I would avoid it if it all possible.

JK and JBD seem to be what most people are happy with, not cheap but reliable.

 

[Zwy]

Hello everyone,

I appreciate you taking a look at my post and any input you may have.

In short, I'm aiming to build a "small" DIY solar generator with the goal of making a unit that looks good, is durable and relatively neatly packaged to use a container. This is more of a hobby but would use it for occasional camping/RV trips. In watching Will Prowse's video on Chins, he seems to be impressed by it for it's price point but I find that the casing is quite large for a 100ah battery. Is there any reason I simply couldn't remove it from the case (such as he did in his tear down) and secure it in the DIY case I plan to use for my "generator"? It looks like there is a a few extras inches of foam all around and space will be at a premium.

I had planned to build my own 230ah battery until I saw how compact that Chins was especially with the BMS attached. My calculations show about $0.24 cents for DIY vs $.29 for chins. I may consider buying two, removing them from the package and placing them in parallel. Thoughts?

Thanks all!

I had cells and Overkill BMS to build trolling batteries for my boat.

In the end, I bought 2 Zoom 100Ah batteries and repurposed the BMS and cells for other projects. Smartest move I could have made, it would have been more money plus time to DIY my own batteries.

And yes, I'm a firm believer in DIY for larger packs. But for a 12V 100Ah, it's time and cost effective to just buy a built battery.