110v conversion for 36v Macallister battery charger?

[keithb]

We have two 5yr old nano bromptons which we have routinely taken to the US by plane using the original 4ah batteries supplied which have now died

Bought 36v 4ah Mac batteries and charger but latter needs 220v

Any ideas on modifying charger for 110v input?

 

[KirstinS]

Two suggestions for you

1. Use you old charger (any 36v lithium charger can charge any 36v lithium battery, ) just cut off the connector and solder a new one on. Maplin stock most. Post photos of your old charger and new battery socket and I'll help, no worries

2. Buy a US to UK step up converter, something like

https://www.google.co.uk/search?rlz=1CDGOYI_enGB593GB594&hl=en-US&biw=320&bih=492&tbm=shop&ei=4kw2VaXyDo2v7AbDvoHYBw&q=110v+to+240v+step+up+&oq=110v+to+240v+step+up+&gs_l=mobile-gws-serp.12..41j0.37046.38426.0.38861.11.10.0.0.0.9.488.2632.0j2j6j1j1.10.0.msedr...0...1c..64.mobile-gws-serp..10.1.240.7KZLni1ZmJA#spd=4827237109407252818

 

[KirstinS]

Actually I am assuming that both your old and new packs are lithium, 36v and have a BMS for option 1 to work

 

[KirstinS]

Just looked at nano website and it looks like repurposed drill batteries are used

Just buying a step up transformer seems the simplest option in this case

http://pages.ebay.com/link/?nav=item.view&alt=web&id=311253196683

 

[KirstinS]

Sorry for the rambling !

Assuming a 2.5a 36v charger you need 105w

So best to double that and get a 200w converter

http://www.bambuzo.com/uk/catalog/product/view/id/1128135/s/trigear-tg-200w-200-watt-step-up-down-voltage-transformer-converter-ac-110-220-v-or-110-220-volt/?gclid=CMODrIfFh8UCFULJtAodzVYAow

 

[keithb]

Hi Kirstin

Thanks for all the replies!

I want to avoid a step up transformer as they are so heavy

May go with a 12v inverter as I will be driving anyway and probably lighter

Thinking a trying out original charger but still not totally convinced that all Li chargers are equal!

 

[KirstinS]

If you can get away with a 150w it's much smaller

A powerful enough 12v inverter seems even bigger ?

You are right - not all equal but as long as lithium specific and rated at 36v ( so 42v output) and you test with a multimeter should all be ok