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I have built a 3s 156 p Samsung 22p pack to use as a house battery in my van. I'm trying to find a charger for it. Currently I am using my balance charger tenergy tb6b. Here is a screenshot with the data sheet on it. How would I use this information to calculate charge current and any recommendations on a charger. So I need to find an AC/DC charger for it when on shore power and considering the Genasun GV-10 for solar charging.

Thanks in advance!!!

data sheet

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    \$\begingroup\$ Says right in the datasheet <2150 mA/cell. Take that times 156 and keep below that. Anyhow, the busbars required, quite substantial fuses and fire hazards to deal with to start with should be your first concern if you intend to supply and discharge them even close to that. How will you balance them? \$\endgroup\$
    – winny
    Sep 15 '17 at 20:02
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    \$\begingroup\$ @winny has answered for the max charge rate, but this is quite an expensive battery, so if its lifetime matters you may get a longer life by charging more conservatively. Divide the capacity by the "standard" charging time to give a kinder charge current per cell. Multiply that by 156. \$\endgroup\$ Sep 15 '17 at 20:41
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    \$\begingroup\$ What bothers me is that this pack aims at a 4kWh device, which is only a bit shy of electrical cars, maybe for a golf cart. The car manufacturers employ whole divisions of seasoned engineers to design manageable batteries, and their entire business depends on them. What makes you think that a simple connection of 156 cells in parallel will work for more than few charge cycles, and won't rapidly vent into flames burning you and your van? \$\endgroup\$ Sep 15 '17 at 21:18
  • \$\begingroup\$ It is going to be essential to use some type of thermal management on a pack this big. Cells in the middle will not be able to cool since they are surrounded by other hot cells. There is a lot of engineering to a pack like this. I urge you to be cautious and do as much studying as you can. \$\endgroup\$
    – mkeith
    Sep 16 '17 at 0:53
  • \$\begingroup\$ I'm preparing for thermal issues by placing a temperature probe at the center of the pack with for cooling fans to sucking to blowing hahaha and a temperature cutoff switch. I am looking for a charging unit that may help me with this. This is not being used as an electric vehicle battery but as a powerwall in a van to power lights a water pump charger computer charge cell phones and run a very low-power refrigerator. \$\endgroup\$ Sep 16 '17 at 2:06
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You "could" charge at 2150mA * 156p = 335.4A or using CC to 4.2V then off at 10% of CC, but this is not wise over the lifetime of the battery as cells fail the rest must take up the current which accelerates failure of the while pack. Even with this being 2x nominal current of 167.7A only saves 0.5hr/3hr or 16% of the time.

It is wise to use nominal current and this power represents 168A*4.2V*3 = 2.1kW.

A 140W Solar Charger is only 6.6% of your storage capacity and there can be significant charging losses in the battery and charger. This might support 1kWh per day of use assuming > 8 hrs of full sun per day with solar tracking.

Choices of charger and Solar power source require that you define your Solarity index and Energy consumption patterns max/day, avg per week and budget for a power source + charger.

The van's engine alternator might be a good source if avail. with 4.2V*3 = 12.6V from 14.2V using a LiPo regulator with balancer. Dodge Van alternators can be upgraded to 180A I believe and if there is room to add a 2nd alternator, it can be modded to act as an exclusive LiPo charger.

p.s.

I assume you have the skills to make this safe and reliable. Otherwise, better check your Van insurance for fire from DIY battery failures.

Multiple Thermal sensing is critical with intelligent power management.

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  • \$\begingroup\$ Thanks a ton for your post Tony. I don't think I will be charging it that high of amperage (167) but my van does come with a 180 amp alternator:-) there's also the option for a 220 amp. My goal is to have three charging sources I'm well aware that the solar at 4 100 watt panels will charge this battery pretty slowly. I doubt that I'll rarely see a discharge over 100 amps as I will not be using power tools and things like that with it. The goal was to be able to have a large amount of power to sustain me in outdoor endevours . I wanted something small instead of using lead acid. \$\endgroup\$ Sep 16 '17 at 2:18
  • \$\begingroup\$ Also with the solar charger the company steered me towards the 3000i by blue sky solar. Which is a 400 watt charger \$\endgroup\$ Sep 16 '17 at 2:24
  • \$\begingroup\$ You might still want to think about using a van alternator for charging too but the challenge is using a low cost regulator $10 to drive a surplus 2nd surplus alternator dedicated to LiPo CC , CV and float using the field current control input. Possible but never seen anyone do it. Adding the 2nd alternator is the easy part. dodgeforum.com/forum/… \$\endgroup\$ Sep 16 '17 at 5:08

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