Bantam BC8DX Charger Review

Jamie Cole tests out the latest ‘must have’ Bantam BC8DX charger to see if charging can be twice the fun it used to be!

 BC8DX_01

So what makes the Bantam BC8DX such an interesting and different charger? Well there are two answers, one is watts and the other is the dual output meaning you can charge two cells at once. Not to mention the fact your lovely little LiPos deserve a good quality balancing charger!

Bantam BC8DX features:

  • Two outputs of 160 Watts each
  • 12 Volt Input with crocodile clips
  • 1s to 8s LiXX batteries
  • Integrated balancing boards
  • Back lit screen
  • USB Connectivity
  • Temperature sensor
  • 320 Watt charging power in total
  • Fan cooled
  • Charging for Li-ion, LiPo, LiFe, NiCad, NiMH, Pb

A point to note in this review is that we will be looking primarily at the LiPo charging capabilities and applications, however the charger does has some fantastic NiCad and NiMH charging features, some of which I have never seen before and have proved to be very good in testing to get the most out of the NiCad packs.

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New Batteries & Watts

So what’s the importance of the new batteries? Well the latest set of cells such as the new FlightPower Eon-X have the ability to charge a 5C with minimum impact on cycle life. So what does this mean in practice, it means you can charge your LiPo from discharged to charged in 15 to 20 minute. To put this in to context of the batteries if you have one of the latest Flightpower EON-X packs and an 11.1V 2200mAh pack this means you can charge it at 11amps! Which is insane? But very handy if you need to fly at the field or don’t want to spend seven hours like me charging packs at 1C.

So this means I could charge my fleet of cells, based on 15 minute charging in under an hour, based on two out puts! You see life changing, this will change my life in many ways, one I wont have to spend several days charging cells and two it means the seven really annoying beeps and the bollocking that follows for annoying everyone will be condensed into a shorter space of time, meaning I am in the dog house for one an hour or so at a time! So the theory goes anyway! All this is a little tongue in check as the charger maxes out at 9 Amps charging rate or 160 watts, but you get the general just of what a charger like this means, especially when coupled with the capable cells.

 BC8DX_03

So why the new cells are relevant to this charger? The question is not so much why as WATT (really bad pun). You may have a charger that claims to charge up to 5 Amps, but can it! If it’s a 50 Watt charger then it might well charge a four cell NiCad at 5 Amps but it cant do a 6s LiPo at 5 Amps, in fact the best it could hope for, being a 50 Watt charger is 1.9 amps when full charged on a 50 Watt charger. So how do we work this out, well time for a really poor maths lesson from me:

  • (Volt) X (Amps) = (Watts)
  • C Rating, max charging rate = (C rating of pack) X (capacity in Amps)
  • Maximum pack voltage = (4.2Volts) X (S count of pack)

If we take the example of the 11.1V 3s EON-X 2200 with 5C charging capability then we end up with the following:

  • (5C) X (2.2Amp capacity pack) = 11 Amps.
  • (4.2V) X (3s Pack) = 12.6V

So the Watts of a charger to charger a 3s 5C pack at 11 amps is as follows:

  • (12.6Volt) X (11Amps) = 138.6 Watts

So you can see you need quite some charger to charge at these high charging rates. In the case of the Bantam BC8DX you can see it can hit out a hell of charge rate. Obviously the higher the cell count or voltage the less the peak charge rate would be when you get up to 8S the peak charge rate is actually 5.4 Amps, but for most cells that I use this is charging at greater then 1C so it will be cooked in under and hour, and you can do two at once.

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Charger Run Through

You have some lone power leads to the charger that have crocodile clips attached this then leads to the left of the unit. You have two outputs with two sets of balance boards allowing for the balancing of up to 8 cells for LiPo’s, one set of out puts is on the left, this is out put 1 and the other set is on the right with output 2. Each side has a slot of a temperature sensor and on the right is the connection to the USB cable to connect the unit to the PC. Towards the back of the unit are the cooling fans which are on both sides cresting a cooling duct for the charger.

Moving to the front of the charger you have a large back light screen and two buttons either side with four buttons under the screen with arrows to increase and decrease values as needed.

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Navigation Through The Menus

Navigating through the menus is quite simple. Turn the unit on, press start or enter and the you are asked to select cell type, before you go any further there is an arrow at the top of the screen to point to which out put you are currently changing the options for, output 1 or 2. If you want to change the out put channel you simple press the ‘Channel’ button and switch sides, this can be done at any time to check the status of a channel or cell.

From here you press enter on the cell type, in this case LiPo and the you are presented with the main screen, the first step is to hit the ‘Mode’ button and to select the charge mode, the different types of which are detailed below, from here you scroll through the menus detailing the cell information, from max capacity to cell count to charge rate. Press enter, the charger does a quick cell count and sanity check asking you to confirm and then hit enter once again if correct. There you have it, one charging battery. Now here is where it gets interesting. If during the charge you hit the arrow key you can scroll to a graph of the voltage status of the cells since the charge began, and then can continue to scroll through to see the individual cell voltage as well as other stats.

I am not going to bore you all again with why, but make sure you are balance charging these lipos cells. The reason behind it is quite simply that most of the charging is based on an overall cell voltage and LiPo cells should never go over 4.21 Volts per cell, if you had two cells in a pack and one was 4.1 and another was 4.3 to give a combined charged voltage 8.4 Volts then pack would be charged as far as the charger is concerned but one cell is in danger of be damaged, or worst case exploding.

Keeping the cells balanced will also ensure a long and prosperous life for your cells. Okay so back to the Bantam charger Menus.

LiPo Charge – This is a straight forward LiPo charge menu, does what it says on the tin. Select the charge current, number of cells and hit the start button. This would be used in conjunction with a stand alone balancer, such as a V Balancer.

LiPo Balance – A fantastic feature of this charger, a built in balancer. But most importantly a built in balancer with adapters available (not supplied) to fit most cell types and combinations.

LiPo Fast charge – Any LiPo charger worth its weight will ramp down the charge current toward the end of the cycle to get the full capacity in to it. If this ramp down does not occur the cells will quite simply hit the peak voltage before they receive a full capacity charge. The fast charge allows you to do away with this final part of the charge cycle leaving your cells giving full voltage but with out the full capacity by approximately 90%. This mean you can charge your cells in record time given the fast charge and the 5C ratings!

LiPo Storage – If you are leaving your cells for a few weeks with out being used then put them on a storage charge. It leaves them at a 70% charge state of 3.85V per cell.

If you leave for cells fully charged for longer periods you will notice they might not have that edge! It will come back after a cycle of the cells but if you leave them at 70% charge using this storage function of the charger you can just charge the cells with that final 30% nearer when you are ready to use them.

This cycle will charge or discharge the cells to the storage voltage requirement.

LiPo Discharge – Quite simply a discharge cycle. You can discharge at a rate of up to 25 Watts per channel.

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What’s It Like To Actually Use?

It’s relatively simple and straight forward. For the LiPo charging I did have to refer to the instructions a couple of times when discharging some cells as there are a number of functions, but other then that you could probably pick it up with a vague understanding of what to do and get on absolute fine. I find some of these chargers a little hard to program but this one follows very intuitively. The back lit screen is also a massive help.

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PC Connectivity

Now I can’t really go in to too much detail as if I did this would take up most of the magazine in the features etc that you get.

I installed this PC software on my laptop, connected it up and then started charging one battery, and discharging a receiver LiPo to test its capacity. I left tit there for an hour and came back to it later on. The level of detail is amazing.

If you have a suspicious pack or you are not sure on some thing then this will help you sus it out straight away. The data logged will give you info on each cell at each stage of the charge cycle, just hover the cursor over the graph and the time you want to know and there it is. Clever stuff and very handy when you want to check on monitor something. Plus you can save and log the info for future reference.

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The Verdict…

Will it change my life? Well I should be able to get more sleep and not have to stay up quite as long charging with the high power output and the dual out put.

My only criticism is it would have been nice to get to 200 Watts per channel, but then you realise that it would require milk float batter to power it up or even a massive transformed to manage 400 Watts coming out of it. Even at the current ratings I am pushing my 20 Amp 14.4 Volt power supply to the limit. So in reality this is as good as it gets.

I love it, it’s a space saver and a money saver, a half decent 150+ Watt charger will cost you north of £150, especially when supplied with the USB connectors etc. So for this to be around the £300 mark is a great value for money purchase when you consider you are getting 2 x 8s chargers that are fully loaded. So it’s cost effective and easy to use.

I bought this with my own hard earned money and so far everyone that has seen this charger has also looked at it, dribbled a bit and muttered that they ‘WANT one’, no, ‘NEED one’. It’s an investment for me that will help make my LiPos last and save me time when I am flying and not flying by giving me two chargers in one simple easy to use unit.

The Bantam BC8DX charger is available from all good model shops priced £289.99. For more information visit the UK distributor’s website at www.energonsolutions.co.uk

 

 

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