Hi guys I am looking for a LIPO battery for a BeeBot. The battery size is roughly 34x30x6 it is a 3.7v 500mAh. Full river is the make and other info I have is Silverlit 753032 MT5C and 140913-18 but am having trouble finding a replacement.
This battery will indeed work. The wiring however for these lipos is only rated at 1A. I see the charge rate of your battery shield is max 1A which would be a little to high for this lipo and wires. I’d recommend charging at around 400mA which corresponds to the lipo capacity and is suitable for the wiring too.
The way these jumpers work is usually by setting the voltage on a pin with a resistor divider. If you’ve got one of these shields already, you could lookup the datasheet for the charge IC and swap out the resistors for a higher value which will set the charge current you need.
It’s much easier (but less educational!) to switch to a bigger battery or a different shield though.
You can try your luck with pointing your phone camera at your screen, but I’ve found the best way is to screenshot it and email it to myself, then import it into google translate (select camera, then import in the bottom right) - it gets the clearest image of the text and so gives the best results.
And here’s another section of interest a bit further down…
So, now we can see that actually, according to the datasheet this charging shield is wrong! Leaving the jumper open will indeed charge at about 1 amp, but shorting the jumper tries to push the charger well past its limits by drawing 1.6 Amps (1100 / 680 = 1.62A)! The charge IC is only rated to 1.2Amps max!
However, in my googling I discovered there’s a very similar version of this chip, the TP5410 TP5410.PDF (855.5 KB)
Which has a different formula for charge current based on RPROG:
The values for this IC actually match up with what they’ve used on the board (680 Ohms for 1A, 1.36k for 0.5A) - so perhaps they used to use the TP5400, and now use the TP5410? Then everything would all make sense.
If your board says TP5410 on it, then you should be able to desolder those two charge resistors and replace it with one that will set a suitable charge current for your battery, say 350mA.
To be honest though, unless there’s some strong reason to use the Wemos D1, Grab a Pico with headers and the CE Piicodev Adapter thing. It’s got a charge IC on it that will work out of the box with your 400mAh battery, and those guys have definitely done things right, as well as the Pico itself being very well supported.
Thanks so very much for all the trouble you’ve gone to to reply to my post . I have to admit to not 100% understanding all the electronics theory but I did check the battery shield and can confirm the name on the chip is TP5400. So in that case, just to confirm, should it be able to charge the LiPo battery I purchased from Core Electronics? Ta.
Yes it is a problem. My way out of it is to try not to purchase anything from China but finding such products can be frustrating.
The second line of defence is if a supplier cannot provide data in English for a product then find a supplier that can.
Even if a particular product has to be made in China I prefer to pay a bit more and purchase locally as I have found the Chinese mail system really sucks. And in a lot of cases the cost is not that much more.